Mattson Technology (MTSN) 10-Q 6 May 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 29, 2015	4-May-15
Document and Entity Information
Entity Registrant Name	MATTSON TECHNOLOGY INC
Entity Central Index Key	928421
Current Fiscal Year End Date	-19
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	29-Mar-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Amendment Flag	FALSE
Entity Common Stock, Shares Outstanding		74,868,670

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Operations (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 29, 2015	Mar. 30, 2014
Income Statement [Abstract]
Net revenue	$58,254	$43,198
Cost of goods sold	36,860	28,552
Gross margin	21,394	14,646
Operating expenses:
Research, development and engineering	5,250	4,524
Selling, general and administrative	8,841	7,421
Total operating expenses	14,091	11,945
Income from operations	7,303	2,701
Interest income (expense), net	-34	-126
Other income (expense), net	-443	79
Income before income taxes	6,826	2,654
Provision for income taxes	521	189
Net income	$6,305	$2,465
Net income per share:
Basic (in usd per share)	$0.08	$0.04
Diluted (in usd per share)	$0.08	$0.04
Shares used in computing net income per share:
Basic (in shares)	74,700	66,275
Diluted (in shares)	77,265	67,971

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 29, 2015	Mar. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income	$6,305	$2,465
Other comprehensive income (loss)
Changes in foreign currency translation adjustments	-1,534	-616
Other comprehensive income (loss)	-1,534	-616
Comprehensive income	$4,771	$1,849

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Mar. 29, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$26,446	$22,760
Accounts receivable, net of allowance for doubtful accounts of $791 as of March 29, 2015 and $669 as of December 31, 2014	38,216	33,578
Advance billings	4,388	4,653
Inventories	38,174	40,579
Prepaid expenses and other current assets	9,188	9,767
Total current assets	116,412	111,337
Property and equipment, net	9,248	7,534
Restricted cash	1,974	1,993
Other assets	548	623
Total assets	128,182	121,487
Current liabilities:
Accounts payable	21,844	22,434
Accrued compensation and benefits	5,112	4,601
Deferred revenues, current	9,213	9,110
Other current liabilities	6,939	6,630
Total current liabilities	43,108	42,775
Deferred revenues, non-current	957	1,160
Other liabilities	2,494	2,442
Total liabilities	46,559	46,377
Commitments and contingencies (Note 6)
Stockholders' equity:
Preferred stock, 2,000 shares authorized; none issued and outstanding	0	0
Common stock, par value $0.001, 120,000 shares authorized; 79,183 shares issued and 74,859 shares outstanding as of March 29, 2015; 78,267 shares issued and 74,009 shares outstanding as of December 31, 2014	79	78
Additional paid-in capital	689,912	687,871
Accumulated other comprehensive income	16,637	18,171
Treasury stock, 4,324 shares as of March 29, 2015 and 4,258 shares as of December 31, 2014	-38,383	-38,083
Accumulated deficit	-586,622	-592,927
Total stockholders' equity	81,623	75,110
Total liabilities and stockholders' equity	$128,182	$121,487

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 29, 2015	Dec. 31, 2014
In Thousands, except Share data, unless otherwise specified
Current assets:
Accounts receivable allowance for doubtful accounts	$791	$669
Stockholders' equity:
Preferred stock, shares authorized (in shares)	2,000,000	2,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value per share (in usd per share)	$0.00	$0.00
Common stock, shares authorized (in shares)	120,000,000	120,000,000
Common stock, shares issued (in shares)	79,183,000	78,267,000
Common stock, shares outstanding (in shares)	74,859,000	74,009,000
Treasury stock, shares (in shares)	4,324,000	4,258,000

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 29, 2015	Mar. 30, 2014
Cash flows from operating activities:
Net income	$6,305	$2,465
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	610	733
Stock-based compensation	516	298
Other non-cash items	253	101
Changes in assets and liabilities:
Accounts receivable	-4,820	-10,892
Advance billings	265	-525
Inventories	-757	-9,649
Prepaid expenses and other assets	57	-3,100
Accounts payable	-340	2,674
Accrued compensation and benefits and other current liabilities	823	2,900
Deferred revenue	-100	1,629
Other liabilities	138	-95
Net cash provided by (used in) operating activities	2,950	-13,461
Cash flows from investing activities:
Purchases of property and equipment	-458	-403
Other	0	10
Net cash used in investing activities	-458	-393
Cash flows from financing activities:
Repayment of revolving credit facility	0	-14,000
Proceeds from issuance of common stock, net	1,225	31,126
Net cash provided by financing activities	1,225	17,126
Effect of exchange rate changes on cash and cash equivalents	-31	-507
Net increase in cash and cash equivalents	3,686	2,765
Cash and cash equivalents, beginning of period	22,760	14,578
Cash and cash equivalents, end of period	26,446	17,343
Supplemental disclosure of non-cash transactions:
Transfer of inventories into property and equipment	$1,988	$0

BASIS_OF_PRESENTATION_AND_SIGN

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 29, 2015
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES
	Nature of Operations
	Mattson Technology, Inc. (referred to in this Quarterly Report on Form 10-Q as "Mattson," "we," "us," or "our") was incorporated in California in 1988 and reincorporated in Delaware in 1997. We design, manufacture, market and globally support semiconductor wafer processing equipment used in the fabrication of integrated circuits.
	Basis of Presentation
	The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") for interim financial information and with the instructions to Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by such accounting principles for complete financial statements. In the opinion of management, all adjustments (which include normal recurring adjustments) considered necessary to present fairly each of the statement of financial position as of March 29, 2015, the statements of operations for the three months ended March 29, 2015 and March 30, 2014, statements of comprehensive income for the three months ended March 29, 2015 and March 30, 2014, and the statements of cash flows for the three months ended March 29, 2015 and March 30, 2014, as applicable, have been made. The condensed consolidated balance sheet as of December 31, 2014 has been derived from our audited financial statements as of such date, but does not include all disclosures required by U.S. GAAP. The accompanying unaudited condensed consolidated financial statements should be read in conjunction with our audited consolidated financial statements for the year ended December 31, 2014, which are included in the Annual Report on Form 10-K filed with the Securities and Exchange Commission on March 12, 2015.
	The condensed consolidated financial statements include the accounts of Mattson Technology, Inc. and our wholly-owned subsidiaries. All inter-company balances and transactions have been eliminated.
	The results of operations for the three months ended March 29, 2015 are not necessarily indicative of results that may be expected for the entire year ending December 31, 2015.
	Fiscal Year
	Our fiscal year ends on December 31. We close our first fiscal quarter on the Sunday closest to March 31. Our second and third fiscal quarters are each 13 weeks long and our fourth quarter closes on December 31.
	Use of Estimates
	The preparation of the condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reported periods. We evaluate our estimates on an ongoing basis, including those related to the useful lives and fair value of long-lived assets, estimates used to determine facility lease loss liabilities, measurement of warranty obligations, valuation allowances for deferred tax assets, the fair value of stock-based compensation, estimates for allowance for doubtful accounts, and valuation of excess and obsolete inventories. Our estimates and assumptions can be subjective and complex and, consequently, actual results could differ materially from those estimates.
	Reclassifications
	For presentation purposes, certain prior period amounts have been reclassified to conform to the reporting in the current period financial statements. These reclassifications do not affect our net income, cash flows or stockholders' equity.
	Recent Accounting Pronouncements
	In April 2015, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2015-03, Simplifying the Presentation of Debt Issuance Costs. Debt issuance costs are specified incremental costs, other than those paid to the lender, that are directly attributable to issuing a debt instrument (i.e., third party costs). Prior to the adoption of this standard, debt issuance costs were required to be presented in the balance sheet as a deferred charge (i.e., an asset). This presentation differed from the presentation for a debt discount, which is a direct adjustment to the carrying value of the debt (i.e., a contra liability). This new standard requires that all costs incurred to issue debt be presented in the balance sheet as a direct deduction from the carrying value of the debt. This new standard does not affect the recognition and measurement of debt issuance costs. ASU 2015-03 will be effective for us in the first quarter of fiscal 2016, with early adoption permitted. We are currently evaluating the impact that the implementation of this standard will have on our financial statements.
	In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers. The FASB issued ASU 2014-09 to clarify the principles for recognizing revenue and to develop a common revenue standard for GAAP and International Financial Reporting Standards. The standard outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes the most current revenue recognition guidance. This guidance is effective for fiscal years and interim periods within those years beginning after December 15, 2016, which is effective for us as of the first quarter of our fiscal year ending December 31, 2017. On April 1, 2015, the FASB agreed to propose delaying the effective date by one year. We are currently evaluating the impact that the implementation of this standard will have on our financial statements.
	There were no other recent accounting pronouncements or changes in accounting pronouncements during the three months ended March 29, 2015 compared to the recent accounting pronouncements described in our Annual Report on Form 10-K for the fiscal year ended December 31, 2014 that are of significance or potential significance to us.

BALANCE_SHEET_DETAILS

BALANCE SHEET DETAILS	3 Months Ended
	Mar. 29, 2015
Balance Sheet Related Disclosures [Abstract]
Balance Sheet Details	BALANCE SHEET DETAILS
	We had restricted cash of $2.0 million and $2.0 million as of March 29, 2015 and December 31, 2014, respectively, which is primarily related to secured standby letters of credit for our long-term leases. Accordingly, such amounts are classified as long term in the accompanying condensed consolidated balance sheets. See Note 6. Commitments and Contingencies.
	Components of inventories as of March 29, 2015 and December 31, 2014 are shown below (in thousands):
		March 29,			December 31,
		2015			2014
	Inventories:
	Purchased parts and raw materials	$	28,609		$	28,143
	Work-in-process	6,923			10,832
	Finished goods	2,642			1,604
		$	38,174		$	40,579
	Components of prepaid expenses and other current assets as of March 29, 2015 and December 31, 2014 are shown below (in thousands):
		March 29,			December 31,
		2015			2014
	Prepaid expenses and other current assets:
	Value-added tax	$	3,230		$	4,184
	Other current assets	5,958			5,583
		$	9,188		$	9,767
	Components of property and equipment as of March 29, 2015 and December 31, 2014 are shown below (in thousands):
		March 29,			December 31,
		2015			2014
	Property and equipment, net:
	Machinery and equipment	$	42,674		$	40,777
	Furniture and fixtures	8,666			9,079
	Leasehold improvements	16,924			17,646
		68,264			67,502
	Less: accumulated depreciation	(59,016		)	(59,968		)
		$	9,248		$	7,534
	Components of other current liabilities as of March 29, 2015 and December 31, 2014 are shown below (in thousands):
		March 29,			December 31,
		2015			2014
	Other current liabilities:
	Warranty	$	3,343		$	2,803
	Value-added tax	1,071			1,547
	Accrued restructuring charge, current	148			366
	Other	2,377			1,914
		$	6,939		$	6,630

FAIR_VALUE_MEASUREMENT

FAIR VALUE MEASUREMENT	3 Months Ended
	Mar. 29, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurement	FAIR VALUE MEASUREMENT
	We measure certain assets and liabilities at fair value, which is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability. The authoritative guidance on fair value measurements establishes a three-tier value hierarchy, which prioritizes the inputs used in measuring fair value as follows:
	Level 1. Quoted prices (unadjusted) in active markets for identical assets or liabilities.
	Level 2. Include other inputs that are directly or indirectly observable in the marketplace.
	Level 3. Unobservable inputs that are supported by little or no market activities.
	Our money market funds are classified within Level 1 of the fair value hierarchy, as these instruments are valued using quoted market prices. Specifically, we value our investments in money market securities on quoted market prices in active markets. As of March 29, 2015 and December 31, 2014, we had no assets or liabilities classified within Level 2 or Level 3 and there were no transfers of instruments between Level 1, Level 2 and Level 3 regarding fair value measurement.
	Cash and cash equivalents and restricted cash are carried at fair value. Accounts receivable and accounts payable are valued at their carrying amounts, which approximate fair value due to their short-term nature.
	Assets and Liabilities Measured at Fair Value on a Recurring Basis
	Assets and liabilities measured at fair value on a recurring basis are shown in the table below by their corresponding balance sheet caption and consisted of the following types of instruments as of March 29, 2015 and December 31, 2014 (in thousands):
		March 29, 2015				December 31, 2014
		Fair Value Measurements at				Fair Value Measurements at
		Reporting Date Using				Reporting Date Using
		(Level 1)		Total		(Level 1)		Total
	Assets measured at fair value:
	Cash equivalents:
	Money market funds	$	15,008	$	15,008	$	7,007	$	7,007
	Restricted cash:
	Money market funds	1,806		1,806		1,806		1,806
	Total assets measured at fair value	$	16,814	$	16,814	$	8,813	$	8,813

REVOLVING_CREDIT_FACILITY

REVOLVING CREDIT FACILITY	3 Months Ended
	Mar. 29, 2015
Debt Disclosure [Abstract]
Revolving Credit Facility	REVOLVING CREDIT FACILITY
	On April 12, 2013, we entered into a three-year $25.0 million senior secured revolving credit facility with Silicon Valley Bank. On October 21, 2014, we entered into Amendment Agreement No. 4 with Silicon Valley Bank, which (i) extended the term of our credit facility to October 12, 2017, (ii) amending and/or waiving compliance with certain financial covenants, and (iii) granted us the ability to make a one-time request to increase the existing credit facility up to an additional $25.0 million. As of March 29, 2015 and December 31, 2014, we had no outstanding borrowings under the credit facility.
	For a further discussion of our credit facility, see Note 5. Revolving Credit Facility in the notes to the consolidated financial statements in our Annual Report on Form 10-K for the year ended December 31, 2014.

RESTRUCTURING_AND_OTHER_CHARGE

RESTRUCTURING AND OTHER CHARGES	3 Months Ended
	Mar. 29, 2015
Restructuring Charges [Abstract]
Restructuring and Other Charges	RESTRUCTURING AND OTHER CHARGES
	In December 2011, our management approved and initiated a cost reduction plan ("2011 Restructuring Plan") as part of a broad-based cost reduction initiative. The 2011 Restructuring Plan included the consolidation of our manufacturing and research and development facilities, including contract termination costs related to two vacant facilities; moving a portion of our outsourced spare parts logistics operations in-house; and workforce reductions. We are continuing to make payments related to these restructuring activities through fiscal year 2015.
	As of March 29, 2015 and December 31, 2014, we had accrued restructuring charges of $0.1 million and $0.4 million, respectively, which were classified within other current liabilities in the condensed consolidated balance sheets. During the three months ended March 29, 2015 and March 30, 2014, we did not incur any restructuring and other charges.

COMMITMENTS_AND_CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 29, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES
	Warranty
	The warranty offered by us on our system sales is generally twelve months, and excludes certain consumable maintenance items. A provision for the estimated cost of warranty, based on historical costs, is recorded as cost of goods sold when the revenue is recognized. Our warranty obligations require us to repair or replace defective products or parts during the warranty period at no cost to the customer. The actual system performance and/or field warranty expense profiles may differ from historical experience, and in those cases, we adjust our warranty accruals accordingly.
	The following table summarizes changes in our product warranty accrual for the three months ended March 29, 2015 and March 30, 2014 (in thousands):
		Three Months Ended
		March 29,			March 30,
		2015			2014
	Beginning balance	$	2,803		$	1,786
	Warranties issued in the period	872			552
	Costs to service warranties	(982		)	(583		)
	Warranty accrual adjustments	650			177
	Ending balance	$	3,343		$	1,932
	Guarantees
	In the ordinary course of business, our bank provides standby letters of credit or other guarantee instruments on our behalf to certain parties as required. The standby letters of credit are secured by bank accounts and money market funds, which are classified as restricted cash in the accompanying condensed consolidated balance sheets. We have never recorded any liability in connection with these guarantee arrangements beyond what is required to appropriately account for the underlying transaction being guaranteed. We do not believe, based on historical experience and information currently available, that it is probable that any amounts will be required to be paid under such guarantee arrangements. As of March 29, 2015, the maximum potential amount that we could be required to pay was $1.9 million, the total amount of outstanding standby letters of credit, which were secured by $2.0 million in bank accounts and money market collateral accounts. This amount was recorded as restricted cash as of March 29, 2015.
	In connection with our acquisition of Vortek Industries, Ltd. ("Vortek") in 2004, we became party to an agreement between Vortek and the Canadian Minister of Industries (the "Minister") relating to an investment in Vortek by Technology Partnerships Canada. Under the agreement, as amended, we, or Vortek (renamed Mattson Technology, Canada, Inc. ("MTC")) agreed to various terms, including (i) payment by us of a royalty to the Minister of 1.4 percent of net sales from certain Flash RTP products, up to a total of C$14.3 million (approximately $11.4 million based on the applicable exchange rate as of March 29, 2015), (ii) MTC maintaining a specified average workforce of employees in Canada, making certain investments and complying with certain manufacturing requirements, each, through October 27, 2009, and (iii) certain other covenants concerning protection of intellectual property rights. Under the provisions of this agreement, if MTC is dissolved, files for bankruptcy or we, or MTC, do not materially satisfy the obligations pursuant to any material terms or conditions, the Minister could demand payment of liquidated damages in the amount of C$14.3 million less any royalties paid to the Minister. As of October 27, 2009, we were no longer subject to covenant (ii), as discussed above but are still subject to the remaining terms and conditions until the earlier of payment of royalty of C$14.3 million (approximately $11.4 million based on the applicable exchange rate as of March 29, 2015) or through December 31, 2020. We have recorded approximately C$0.5 million in cumulative royalty charges to date. The movement of our Canadian operations to Germany did not result in the dissolution of MTC.
	We are a party to a variety of agreements, pursuant to which we may be obligated to indemnify other parties with respect to certain matters. Typically, these obligations arise in the context of contracts under which we may agree to hold other parties harmless against losses arising from a breach of representations or with respect to certain intellectual property, operations or tax-related matters. Our obligations under these agreements may be limited in terms of time and/or amount, and in some instances, we may have defenses to asserted claims and/or recourse against third parties for payments made. It is not possible to predict the maximum potential amount of future payments under these or similar agreements due to the conditional nature of our obligations and the unique facts and circumstances involved in each particular agreement. Historically, our payments under these agreements have not had a material effect on our financial position, results of operations or cash flows. We believe if we were to incur a loss in any of these matters, such loss would not have a material effect on our financial position, results of operations or cash flows.
	We indemnify our directors and certain employees as permitted by law, and have entered into indemnification agreements with our directors and certain senior officers. We have not recorded a liability associated with these indemnification agreements, as we historically have not incurred any material costs associated with such indemnification agreements. Costs associated with such indemnification agreements may be mitigated, in whole or only in part, by insurance coverage that we maintain.
	Litigation
	In the ordinary course of business, we are subject to claims and litigation, including claims that we infringe third party patents, trademarks and other intellectual property rights. Although we believe that it is unlikely that any current claims or actions will have a material adverse impact on our operating results or our financial position, given the uncertainty of litigation, we cannot be certain of this. The defense of claims or actions against us, even if without merit, could result in the expenditure of significant financial and managerial resources.
	We record a legal liability when we believe it is both probable that a liability has been incurred, and the amount can be reasonably estimated. We monitor developments in our legal matters that could affect the estimate we have previously accrued. Significant judgment is required to determine both probability and the estimated amount.

EMPLOYEE_STOCK_PLANS

EMPLOYEE STOCK PLANS	3 Months Ended
	Mar. 29, 2015
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Employee Stock Plans	EMPLOYEE STOCK PLANS
	As of March 29, 2015, we had approximately 1.6 million shares available for future grants under our 2012 Equity Incentive Plan (the "2012 Plan").
	Stock Options
	Options to purchase common stock granted under the 2012 Plan generally have terms not exceeding seven years. Options to purchase stock under our equity incentive plans are generally granted at exercise prices that are at least 100 percent of the fair market value of our common stock on the date of grant. Generally, options granted to new employees typically vest over a period of four years at a rate of 25 percent after the first year and 1/48th of the initial amount granted each month thereafter, and beginning in 2014, options granted to established employees with more than 1-year of service, typically vest over a period of four years at a rate of 1/48th each month.
	The following table summarizes the stock option activity under all of our equity incentive plans for the three months ended March 29, 2015:
		Number of Shares		Weighted-			Weighted- Average Remaining Term	Aggregate Intrinsic Value
				Average
				Exercise
				Price
		(thousands)		(per share)			(years)	(thousands)
	Outstanding as of December 31, 2014	4,920		$	2.01
	Granted	586		$	3.3
	Exercised	(740	)	$	2.06
	Forfeited or expired	(210	)	$	4.82
	Outstanding as of March 29, 2015	4,556		$	2.04		4.7	$	8,251
	Exercisable as of March 29, 2015	2,536		$	1.84		3.8	$	5,161
	The aggregate intrinsic value represents the pre-tax differences between the exercise price of stock options and the quoted market price of our stock on March 27, 2015 for all in-the-money options.
	The following table provides supplemental information pertaining to our stock options for the three months ended March 29, 2015 and March 30, 2014 (in thousands, except weighted-average fair values):
		Three Months Ended
		March 29,			March 30,
		2015			2014
	Weighted-average fair value of options granted, per share	$	1.67		$	1.29
	Intrinsic value of options exercised	$	1,940		$	153
	Cash received from options exercised	$	1,526		$	92
	Restricted Stock Units
	The 2012 Plan provides for grants of time-based and performance-based restricted stock units ("RSUs"). As of March 29, 2015, we only had time-based RSUs outstanding.
	Time-Based Restricted Stock Units
	Historically, 25 percent of the time-based RSUs vest on each anniversary of the vesting commencement date or date of grant. In December 2013, our Board of Directors approved a quarterly vesting schedule for RSUs. On occasion, we grant time-based RSUs for varying purposes with different vesting schedules. Time-based RSUs granted under the 2012 Plan are counted against the total number of shares of common stock available for grant under the 2012 Plan at 1.75 shares of common stock for every one share of common stock subject thereto.
	The associated stock-based compensation expense on time-based RSUs is determined based on the fair value of our common stock on the date of grant of the RSU and recognized over the vesting period.
	The following table summarizes RSU activity under all of our equity incentive plans for the three months ended March 29, 2015:
		Number of Shares		Weighted Average Grant Date Fair Value
		(thousands)		(per share)
	Outstanding as of December 31, 2014	877		$	2.06
	Granted	783		$	3.31
	Released	(176	)	$	2.1
	Forfeited	(52	)	$	2.76
	Outstanding as of March 29, 2015	1,432		$	2.71

STOCKBASED_COMPENSATION

STOCK-BASED COMPENSATION	3 Months Ended
	Mar. 29, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	STOCK-BASED COMPENSATION
	We account for stock-based compensation in accordance with the applicable authoritative guidance, which requires the measurement of stock-based compensation on the date of grant based on the fair value of the award, and the recognition of the expense over the requisite service period for the employee. Compensation related to RSUs is the intrinsic value on the date of grant, which is the closing price of our common stock less the employee exercise price, if any. Compensation related to stock options is determined using a stock option valuation model.
	Valuation Assumptions
	We use the Black-Scholes valuation model to determine the fair value of stock options. The Black-Scholes model requires the input of highly subjective assumptions, which are summarized in the table below for the three months ended March 29, 2015 and March 30, 2014:
		Three Months Ended
		March 29,		March 30,
		2015		2014
	Expected dividend yield	—		—
	Expected stock price volatility	66%		68%
	Risk-free interest rate	1.10%		1.40%
	Expected life of options in years	4		4
	We estimate the expected life of options based on an analysis of our historical experience of employee exercise and post-vesting termination behavior considered in relation to the contractual life of the option. Expected volatility is based on the historical volatility of our common stock; and the risk-free interest rate is the rate on a U.S. Treasury Bill, with a maturity approximating the expected life of the option. We do not currently pay cash dividends on our common stock and do not anticipate doing so in the foreseeable future. Accordingly, the expected dividend yield is zero.
	Our stock-based compensation for the three months ended March 29, 2015 and March 30, 2014 was as follows (in thousands):
		Three Months Ended
		March 29,			March 30,
		2015			2014
	Stock-based compensation by type of award:
	Stock options	$	245		$	247
	Restricted stock units	266			39
	Employee stock purchase plan	5			12
		$	516		$	298
	Stock-based compensation by category of expense:
	Cost of goods sold	$	34		$	2
	Research, development and engineering	63			41
	Selling, general and administrative	419			255
		$	516		$	298
	We did not capitalize any stock-based compensation into inventory in the three months ended March 29, 2015 and March 30, 2014, as such amounts were immaterial. As of March 29, 2015, we had $1.8 million in unrecognized stock-based compensation expense, net of estimated forfeitures, related to stock options which will be recognized over a weighted-average period of 2.6 years. As of March 29, 2015, we had $2.8 million in unrecognized stock-based compensation expense, net of estimated forfeitures, related to unvested RSUs which will be recognized over a weighted-average period of 3.1 years.

GEOGRAPHIC_AND_CUSTOMER_CONCEN

GEOGRAPHIC AND CUSTOMER CONCENTRATION INFORMATION	3 Months Ended
	Mar. 29, 2015
Geographic and Customer Concentration Information [Abstract]
Geographic and Customer Concentration Information	GEOGRAPHIC AND CUSTOMER CONCENTRATION INFORMATION
	The authoritative guidance on segment reporting and disclosure defines an operating segment as a component of an enterprise for which separate financial information is available that is evaluated regularly by the chief operating decision maker in deciding how to allocate resources and in assessing performance. For the purposes of evaluating our reportable segments, our Chief Executive Officer is the chief operating decision maker.
	We have one operating segment in which we design, manufacture and market advanced fabrication equipment for the semiconductor manufacturing industry. As our business is completely focused on one industry segment, the design, manufacture and marketing of advanced fabrication equipment to the semiconductor manufacturing industry, management believes that we have one reportable segment. Our net revenue and profits are generated from the sales of systems and services in this one segment.
	The following table summarizes net revenue by geographic areas based on the installation locations of the systems and the location of services rendered (in thousands, except percentages):
		Three Months Ended
		March 29, 2015				March 30, 2014
		Amount		Percent		Amount		Percent
	Net revenue:
	United States	$	8,568	15		$	4,183	10
	South Korea	33,998		58		10,259		24
	China	3,599		6		13,081		30
	Taiwan	5,520		10		10,822		25
	Other Asia	5,365		9		2,281		5
	Europe and others	1,204		2		2,572		6
		$	58,254	100		$	43,198	100
	For the three months ended March 29, 2015, two customers accounted for 10 percent or more of our total net revenue, representing approximately 63 percent and 13 percent of our total net revenue, respectively.
	For the three months ended March 30, 2014, two customers accounted for 10 percent or more of our total net revenue, representing approximately 59 percent and 16 percent of our total net revenue, respectively.
	As of March 29, 2015, two customers accounted for 10 percent or more of our total net accounts receivable, representing approximately 53 percent and 19 percent of our total net accounts receivable, respectively. As of December 31, 2014, one customer accounted for 10 percent or more of our net accounts receivable, representing approximately 74 percent of our total net accounts receivable.
	Geographical information relating to our property and equipment, net, as of March 29, 2015 and December 31, 2014 was as follows (in thousands):
		March 29,		December 31,
		2015		2014
	Property and equipment, net:
	United States	$	4,582	$	4,140
	Germany	4,456		3,185
	Others	210		209
		$	9,248	$	7,534

INCOME_TAXES

INCOME TAXES	3 Months Ended
	Mar. 29, 2015
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES
	On a quarterly basis, we record our income tax expense or benefit based on our year-to-date results and expected results for the remainder of the year.
	We recorded an income tax provision of $0.5 million and $0.2 million for the three months ended March 29, 2015 and March 30, 2014, respectively. The income tax provision for both periods was the result of the mix of profits earned by us in tax jurisdictions with a broad range of income tax rates.

NET_INCOME_LOSS_PER_SHARE

NET INCOME (LOSS) PER SHARE	3 Months Ended
	Mar. 29, 2015
Earnings Per Share [Abstract]
Net Income (Loss) Per Share	NET INCOME PER SHARE
	We present both basic and diluted net income per share on the face of our condensed consolidated statements of operations in accordance with the authoritative guidance on earnings per share. Basic net income per common share is computed by dividing net income by the weighted-average number of shares of common stock outstanding for the period. Diluted net income per share of common stock is computed using the weighted average number of shares of common stock outstanding plus the effect of common stock equivalents, unless the common stock equivalents are anti-dilutive. The potential dilutive shares of our common stock resulting from assumed exercises of equity related instruments are determined using the treasury stock method. Under the treasury stock method, an increase in the fair market value of our common stock will result in a greater number of dilutive securities.
	The following table presents the computation of net income per share of common stock (in thousands, except per share data):
		Three Months Ended
		March 29,		March 30,
		2015		2014
	Numerator:
	Net income	$	6,305	$	2,465
	Denominator:
	Weighted-average shares outstanding - basic	74,700		66,275
	Effect of dilutive stock options and restricted stock units	2,565		1,696
	Weighted-average shares outstanding - diluted	77,265		67,971
	Net income per share of common stock:
	Basic	$	0.08	$	0.04
	Diluted	$	0.08	$	0.04
	For the three months ended March 29, 2015, options and RSUs totaling 0.7 million shares were excluded from diluted net income per share because their inclusion would have been anti-dilutive. For the three months ended March 30, 2014, options and RSUs totaling 1.9 million shares were excluded from diluted net income per share because their inclusion would have been anti-dilutive effect.

SUBSEQUENT_EVENTS

SUBSEQUENT EVENTS	3 Months Ended
	Mar. 29, 2015
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS
	On July 28, 2005, our Board of Directors declared a dividend distribution of one preferred stock purchase right (collectively, the “Rights”) for each outstanding share of common stock, par value $0.001 per share, to stockholders of record at the close of business on August 15, 2005. The description and terms of the Rights are set forth in a Rights Agreement between us and Computershare Trust Company, N.A. (the “Rights Agent”), as successor to Mellon Investor Services, LLC, dated July 28, 2005 (as amended from time to time, the “Rights Agreement”).
	On May 5, 2015, we entered into Amendment No. 3 to Rights Agreement (the “Amendment”) to change the “Final Expiration Date” of the Rights Agreement from July 27, 2015 to May 5, 2015. As a result of the Amendment, effective as of the close of business on May 5, 2015, the Rights expired and were no longer outstanding and the Rights Agreement terminated by its terms.

BASIS_OF_PRESENTATION_AND_SIGN1

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 29, 2015
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation
	The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") for interim financial information and with the instructions to Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by such accounting principles for complete financial statements. In the opinion of management, all adjustments (which include normal recurring adjustments) considered necessary to present fairly each of the statement of financial position as of March 29, 2015, the statements of operations for the three months ended March 29, 2015 and March 30, 2014, statements of comprehensive income for the three months ended March 29, 2015 and March 30, 2014, and the statements of cash flows for the three months ended March 29, 2015 and March 30, 2014, as applicable, have been made. The condensed consolidated balance sheet as of December 31, 2014 has been derived from our audited financial statements as of such date, but does not include all disclosures required by U.S. GAAP. The accompanying unaudited condensed consolidated financial statements should be read in conjunction with our audited consolidated financial statements for the year ended December 31, 2014, which are included in the Annual Report on Form 10-K filed with the Securities and Exchange Commission on March 12, 2015.
	The condensed consolidated financial statements include the accounts of Mattson Technology, Inc. and our wholly-owned subsidiaries. All inter-company balances and transactions have been eliminated.
	The results of operations for the three months ended March 29, 2015 are not necessarily indicative of results that may be expected for the entire year ending December 31, 2015.
Fiscal Year	Fiscal Year
	Our fiscal year ends on December 31. We close our first fiscal quarter on the Sunday closest to March 31. Our second and third fiscal quarters are each 13 weeks long and our fourth quarter closes on December 31.
Use of Estimates	Use of Estimates
	The preparation of the condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reported periods. We evaluate our estimates on an ongoing basis, including those related to the useful lives and fair value of long-lived assets, estimates used to determine facility lease loss liabilities, measurement of warranty obligations, valuation allowances for deferred tax assets, the fair value of stock-based compensation, estimates for allowance for doubtful accounts, and valuation of excess and obsolete inventories. Our estimates and assumptions can be subjective and complex and, consequently, actual results could differ materially from those estimates.
Reclassifications	Reclassifications
	For presentation purposes, certain prior period amounts have been reclassified to conform to the reporting in the current period financial statements. These reclassifications do not affect our net income, cash flows or stockholders' equity.
Recent Accounting Pronouncements	Recent Accounting Pronouncements
	In April 2015, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2015-03, Simplifying the Presentation of Debt Issuance Costs. Debt issuance costs are specified incremental costs, other than those paid to the lender, that are directly attributable to issuing a debt instrument (i.e., third party costs). Prior to the adoption of this standard, debt issuance costs were required to be presented in the balance sheet as a deferred charge (i.e., an asset). This presentation differed from the presentation for a debt discount, which is a direct adjustment to the carrying value of the debt (i.e., a contra liability). This new standard requires that all costs incurred to issue debt be presented in the balance sheet as a direct deduction from the carrying value of the debt. This new standard does not affect the recognition and measurement of debt issuance costs. ASU 2015-03 will be effective for us in the first quarter of fiscal 2016, with early adoption permitted. We are currently evaluating the impact that the implementation of this standard will have on our financial statements.
	In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers. The FASB issued ASU 2014-09 to clarify the principles for recognizing revenue and to develop a common revenue standard for GAAP and International Financial Reporting Standards. The standard outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes the most current revenue recognition guidance. This guidance is effective for fiscal years and interim periods within those years beginning after December 15, 2016, which is effective for us as of the first quarter of our fiscal year ending December 31, 2017. On April 1, 2015, the FASB agreed to propose delaying the effective date by one year. We are currently evaluating the impact that the implementation of this standard will have on our financial statements.
	There were no other recent accounting pronouncements or changes in accounting pronouncements during the three months ended March 29, 2015 compared to the recent accounting pronouncements described in our Annual Report on Form 10-K for the fiscal year ended December 31, 2014 that are of significance or potential significance to us.

BALANCE_SHEET_DETAILS_Tables

BALANCE SHEET DETAILS (Tables)	3 Months Ended
	Mar. 29, 2015
Balance Sheet Related Disclosures [Abstract]
Schedule of Components of Inventories	Components of inventories as of March 29, 2015 and December 31, 2014 are shown below (in thousands):
		March 29,			December 31,
		2015			2014
	Inventories:
	Purchased parts and raw materials	$	28,609		$	28,143
	Work-in-process	6,923			10,832
	Finished goods	2,642			1,604
		$	38,174		$	40,579
Schedule of Components of Prepaid Expense and Other Current Assets	Components of prepaid expenses and other current assets as of March 29, 2015 and December 31, 2014 are shown below (in thousands):
		March 29,			December 31,
		2015			2014
	Prepaid expenses and other current assets:
	Value-added tax	$	3,230		$	4,184
	Other current assets	5,958			5,583
		$	9,188		$	9,767
Schedule of Components of Property and Equipment	Components of property and equipment as of March 29, 2015 and December 31, 2014 are shown below (in thousands):
		March 29,			December 31,
		2015			2014
	Property and equipment, net:
	Machinery and equipment	$	42,674		$	40,777
	Furniture and fixtures	8,666			9,079
	Leasehold improvements	16,924			17,646
		68,264			67,502
	Less: accumulated depreciation	(59,016		)	(59,968		)
		$	9,248		$	7,534
Schedule of Components of Other Current Liabilities	Components of other current liabilities as of March 29, 2015 and December 31, 2014 are shown below (in thousands):
		March 29,			December 31,
		2015			2014
	Other current liabilities:
	Warranty	$	3,343		$	2,803
	Value-added tax	1,071			1,547
	Accrued restructuring charge, current	148			366
	Other	2,377			1,914
		$	6,939		$	6,630

FAIR_VALUE_MEASUREMENT_Tables

FAIR VALUE MEASUREMENT (Tables)	3 Months Ended
	Mar. 29, 2015
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Measured on Recurring Basis	Assets and liabilities measured at fair value on a recurring basis are shown in the table below by their corresponding balance sheet caption and consisted of the following types of instruments as of March 29, 2015 and December 31, 2014 (in thousands):
		March 29, 2015				December 31, 2014
		Fair Value Measurements at				Fair Value Measurements at
		Reporting Date Using				Reporting Date Using
		(Level 1)		Total		(Level 1)		Total
	Assets measured at fair value:
	Cash equivalents:
	Money market funds	$	15,008	$	15,008	$	7,007	$	7,007
	Restricted cash:
	Money market funds	1,806		1,806		1,806		1,806
	Total assets measured at fair value	$	16,814	$	16,814	$	8,813	$	8,813

COMMITMENTS_AND_CONTINGENCIES_

COMMITMENTS AND CONTINGENCIES (Tables)	3 Months Ended
	Mar. 29, 2015
Commitments and Contingencies Disclosure [Abstract]
Summary of Changes in Product Warranty Accrual	The following table summarizes changes in our product warranty accrual for the three months ended March 29, 2015 and March 30, 2014 (in thousands):
		Three Months Ended
		March 29,			March 30,
		2015			2014
	Beginning balance	$	2,803		$	1,786
	Warranties issued in the period	872			552
	Costs to service warranties	(982		)	(583		)
	Warranty accrual adjustments	650			177
	Ending balance	$	3,343		$	1,932

EMPLOYEE_STOCK_PLANS_Tables

EMPLOYEE STOCK PLANS (Tables)	3 Months Ended
	Mar. 29, 2015
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Schedule of Stock Option Activity	The following table summarizes the stock option activity under all of our equity incentive plans for the three months ended March 29, 2015:
		Number of Shares		Weighted-			Weighted- Average Remaining Term	Aggregate Intrinsic Value
				Average
				Exercise
				Price
		(thousands)		(per share)			(years)	(thousands)
	Outstanding as of December 31, 2014	4,920		$	2.01
	Granted	586		$	3.3
	Exercised	(740	)	$	2.06
	Forfeited or expired	(210	)	$	4.82
	Outstanding as of March 29, 2015	4,556		$	2.04		4.7	$	8,251
	Exercisable as of March 29, 2015	2,536		$	1.84		3.8	$	5,161
	The aggregate intrinsic value represents the pre-tax differences between the exercise price of stock options and the quoted market price of our stock on March 27, 2015 for all in-the-money options.
	The following table provides supplemental information pertaining to our stock options for the three months ended March 29, 2015 and March 30, 2014 (in thousands, except weighted-average fair values):
		Three Months Ended
		March 29,			March 30,
		2015			2014
	Weighted-average fair value of options granted, per share	$	1.67		$	1.29
	Intrinsic value of options exercised	$	1,940		$	153
	Cash received from options exercised	$	1,526		$	92
Schedule of Restricted Stock Units	The following table summarizes RSU activity under all of our equity incentive plans for the three months ended March 29, 2015:
		Number of Shares		Weighted Average Grant Date Fair Value
		(thousands)		(per share)
	Outstanding as of December 31, 2014	877		$	2.06
	Granted	783		$	3.31
	Released	(176	)	$	2.1
	Forfeited	(52	)	$	2.76
	Outstanding as of March 29, 2015	1,432		$	2.71

STOCKBASED_COMPENSATION_Tables

STOCK-BASED COMPENSATION (Tables)	3 Months Ended
	Mar. 29, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Valuation Assumptions	The Black-Scholes model requires the input of highly subjective assumptions, which are summarized in the table below for the three months ended March 29, 2015 and March 30, 2014:
		Three Months Ended
		March 29,		March 30,
		2015		2014
	Expected dividend yield	—		—
	Expected stock price volatility	66%		68%
	Risk-free interest rate	1.10%		1.40%
	Expected life of options in years	4		4
Schedule of Stock-Based Compensation	Our stock-based compensation for the three months ended March 29, 2015 and March 30, 2014 was as follows (in thousands):
		Three Months Ended
		March 29,			March 30,
		2015			2014
	Stock-based compensation by type of award:
	Stock options	$	245		$	247
	Restricted stock units	266			39
	Employee stock purchase plan	5			12
		$	516		$	298
	Stock-based compensation by category of expense:
	Cost of goods sold	$	34		$	2
	Research, development and engineering	63			41
	Selling, general and administrative	419			255
		$	516		$	298

GEOGRAPHIC_AND_CUSTOMER_CONCEN1

GEOGRAPHIC AND CUSTOMER CONCENTRATION INFORMATION (Tables)	3 Months Ended
	Mar. 29, 2015
Geographic and Customer Concentration Information [Abstract]
Summary of Net Revenue by Geographic Area	The following table summarizes net revenue by geographic areas based on the installation locations of the systems and the location of services rendered (in thousands, except percentages):
		Three Months Ended
		March 29, 2015				March 30, 2014
		Amount		Percent		Amount		Percent
	Net revenue:
	United States	$	8,568	15		$	4,183	10
	South Korea	33,998		58		10,259		24
	China	3,599		6		13,081		30
	Taiwan	5,520		10		10,822		25
	Other Asia	5,365		9		2,281		5
	Europe and others	1,204		2		2,572		6
		$	58,254	100		$	43,198	100
Summary of Geographic Information Relating to Property and Equipment	Geographical information relating to our property and equipment, net, as of March 29, 2015 and December 31, 2014 was as follows (in thousands):
		March 29,		December 31,
		2015		2014
	Property and equipment, net:
	United States	$	4,582	$	4,140
	Germany	4,456		3,185
	Others	210		209
		$	9,248	$	7,534

NET_INCOME_LOSS_PER_SHARE_Tabl

NET INCOME (LOSS) PER SHARE (Tables)	3 Months Ended
	Mar. 29, 2015
Earnings Per Share [Abstract]
Summary of Computation of Net Income Per Share of Common Stock	The following table presents the computation of net income per share of common stock (in thousands, except per share data):
		Three Months Ended
		March 29,		March 30,
		2015		2014
	Numerator:
	Net income	$	6,305	$	2,465
	Denominator:
	Weighted-average shares outstanding - basic	74,700		66,275
	Effect of dilutive stock options and restricted stock units	2,565		1,696
	Weighted-average shares outstanding - diluted	77,265		67,971
	Net income per share of common stock:
	Basic	$	0.08	$	0.04
	Diluted	$	0.08	$	0.04

BALANCE_SHEET_DETAILS_Narrativ

BALANCE SHEET DETAILS - Narrative (Details) (USD $)	Mar. 29, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Balance Sheet Related Disclosures [Abstract]
Restricted cash	$1,974	$1,993

BALANCE_SHEET_DETAILS_Schedule

BALANCE SHEET DETAILS - Schedule of Components of Inventories (Details) (USD $)	Mar. 29, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Balance Sheet Related Disclosures [Abstract]
Purchased parts and raw materials	$28,609	$28,143
Work-in-process	6,923	10,832
Finished goods	2,642	1,604
Inventories, net	$38,174	$40,579

BALANCE_SHEET_DETAILS_Schedule1

BALANCE SHEET DETAILS - Schedule of Components of Prepaid Expense and Other Current Assets (Details) (USD $)	Mar. 29, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Balance Sheet Related Disclosures [Abstract]
Value-added tax	$3,230	$4,184
Other current assets	5,958	5,583
Prepaid expenses and other current assets	$9,188	$9,767

BALANCE_SHEET_DETAILS_Schedule2

BALANCE SHEET DETAILS - Schedule of Components of Property and Equipment (Details) (USD $)	Mar. 29, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]
Property, and equipment, gross	$68,264	$67,502
Less: accumulated depreciation	-59,016	-59,968
Property and equipment, net	9,248	7,534
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, and equipment, gross	42,674	40,777
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, and equipment, gross	8,666	9,079
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, and equipment, gross	$16,924	$17,646

BALANCE_SHEET_DETAILS_Schedule3

BALANCE SHEET DETAILS - Schedule of Components of Other Current Liabilities (Details) (USD $)	Mar. 29, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Balance Sheet Related Disclosures [Abstract]
Warranty	$3,343	$2,803
Value-added tax	1,071	1,547
Accrued restructuring charge, current	148	366
Other	2,377	1,914
Other current liabilities	$6,939	$6,630

FAIR_VALUE_MEASUREMENT_Narrati

FAIR VALUE MEASUREMENT - Narrative (Details) (USD $)	Mar. 29, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers of assets between Level 1, 2 and 3	$0	$0
Transfers of liabilities between Level 1, 2 and 3	0	0
Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	0	0
Liabilities at fair value	0	0
Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	0	0
Liabilities at fair value	$0	$0

FAIR_VALUE_MEASUREMENT_Schedul

FAIR VALUE MEASUREMENT - Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) (USD $)	Mar. 29, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Assets measured at fair value:
Restricted cash	$1,974	$1,993
Fair Value, Measurements, Recurring | Fair Value Disclosure, Total
Assets measured at fair value:
Total assets measured at fair value	16,814	8,813
Fair Value, Measurements, Recurring | Money Market Funds | Fair Value Disclosure, Total
Assets measured at fair value:
Cash and cash equivalents	15,008	7,007
Restricted cash	1,806	1,806
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Assets measured at fair value:
Total assets measured at fair value	16,814	8,813
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Money Market Funds
Assets measured at fair value:
Cash and cash equivalents	15,008	7,007
Restricted cash	$1,806	$1,806

REVOLVING_CREDIT_FACILITY_Narr

REVOLVING CREDIT FACILITY - Narrative (Details) (Revolving Credit Facility, USD $)	0 Months Ended
	Apr. 12, 2013	Mar. 29, 2015	Dec. 31, 2014	Oct. 21, 2014
Line of Credit Facility [Line Items]
Line of credit facility term	3 years
Line of credit facility, maximum borrowing capacity	$25,000,000
Line of credit facility, outstanding borrowings		0	0
Amended Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility, additional borrowing capacity				$25,000,000

RESTRUCTURING_AND_OTHER_CHARGE1

RESTRUCTURING AND OTHER CHARGES - Narrative (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 29, 2015	Dec. 31, 2014
Restructuring Charges [Abstract]
Restructuring cost recorded to date	$100,000	$400,000
Restructuring and other charges	$0	$0

COMMITMENTS_AND_CONTINGENCIES_1

COMMITMENTS AND CONTINGENCIES - Narrative (Details)	3 Months Ended
	Mar. 29, 2015	Dec. 31, 2014	Mar. 29, 2015	Mar. 29, 2015	Mar. 29, 2015	Mar. 29, 2015
	USD ($)	USD ($)	Financial Standby Letter of Credit	Vortek Industries	Vortek Industries	Vortek Industries
			USD ($)		Royalty Agreements	Royalty Agreements
					USD ($)	CAD
Guarantor Obligations [Line Items]
Length of product warranty on system sales	12 months
Total amount of outstanding standby letters of credit			$1,900,000
Restricted cash	1,974,000	1,993,000
Royalty guarantees payments, percentage of net sales from certain Flash RTP products				1.40%
Potential cash payment to Canadian Minister of Industries from certain Flash RTP products in connection with acquisition of Vortek Industries, Ltd.					11,400,000	14,300,000
Royalty charges to date					$500,000

COMMITMENTS_AND_CONTINGENCIES_2

COMMITMENTS AND CONTINGENCIES - Summary of Changes in Product Warranty Accrual (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 29, 2015	Mar. 30, 2014
Movement in Product Warranty, Increase (Decrease) [Roll Forward]
Beginning balance	$2,803	$1,786
Warranties issued in the period	872	552
Costs to service warranties	-982	-583
Warranty accrual adjustments	650	177
Ending balance	$3,343	$1,932

EMPLOYEE_STOCK_PLANS_Narrative

EMPLOYEE STOCK PLANS - Narrative (Details)	3 Months Ended
	Mar. 29, 2015
Time-based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage vest on each anniversary of the vesting commencement date or date of grant	25.00%
Common stock equivalent shares	1.75
2012 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)	1,600,000
2012 Equity Incentive Plan | Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price, as a percent of fair market value of common stock on grant date	100.00%
Vesting percentage, first anniversary	25.00%
Award ratable vesting percentage per month	2.08%
Requisite service period to vest over 4 years	1 year
Award ratable vesting period	4 years
2012 Equity Incentive Plan | Stock options | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award terms	7 years

EMPLOYEE_STOCK_PLANS_Schedule_

EMPLOYEE STOCK PLANS - Schedule of Stock Option Activity (Details) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 29, 2015
Number of Shares
Outstanding beginning balance (in shares)	4,920
Granted (in shares)	586
Exercised (in shares)	-740
Forfeited or expired (in shares)	-210
Outstanding ending balance (in shares)	4,556
Exercisable (in shares)	2,536
Weighted-Average Exercise Price
Weighted-Average Exercise Price, Outstanding beginning balance (in usd per share)	$2.01
Weighted Average Exercise Price, Granted (in usd per share)	$3.30
Weighted Average Exercise Price, Exercised (in usd per share)	$2.06
Weighted Average Exercise Price, Forfeited or expired (in usd per share)	$4.82
Weighted-Average Exercise Price, Outstanding ending balance (in usd per share)	$2.04
Weighted Average Exercise Price, Exercisable (in usd per share)	$1.84
Weighted Average Remaining Term
Weighted Average Remaining Term, Outstanding	4 years 8 months 7 days
Weighted Average Remaining Term, Exercisable	3 years 9 months 18 days
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Outstanding	$8,251
Aggregate Intrinsic Value, Exercisable	$5,161

EMPLOYEE_STOCK_PLANS_Schedule_1

EMPLOYEE STOCK PLANS - Schedule of Stock Option Activity - Supplemental Information (Details) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 29, 2015	Mar. 30, 2014
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Weighted-average fair value of options granted (in usd per share)	$1.67	$1.29
Intrinsic value of options exercised	$1,940	$153
Cash received from options exercised	$1,526	$92

EMPLOYEE_STOCK_PLANS_Schedule_2

EMPLOYEE STOCK PLANS - Schedule of Restricted Stock Units (Details) (Restricted stock units, USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 29, 2015
Restricted stock units
Number of Shares
Outstanding beginning balance	877
Granted (in shares)	783
Released (in shares)	-176
Forfeited (in shares)	-52
Outstanding ending balance	1,432
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Outstanding beginning balance (usd per share)	$2.06
Weighted Average Grant Date Fair Value, Granted (in usd per share)	$3.31
Weighted Average Grant Date Fair Value, Released (in usd per share)	$2.10
Weighted Average Grant Date Fair Value, Forfeited (in usd per share)	$2.76
Weighted Average Grant Date Fair Value, Outstanding ending balance (in usd per share)	$2.71

STOCKBASED_COMPENSATION_Summar

STOCK-BASED COMPENSATION - Summary of Valuation Assumptions (Details) (Stock options)	3 Months Ended
	Mar. 29, 2015	Mar. 30, 2014
Stock options
Black-Scholes Valuation Assumptions
Expected dividend yield	0.00%	0.00%
Expected stock price volatility	66.00%	68.00%
Risk-free interest rate	1.10%	1.40%
Expected life of options in years	4 years	4 years

STOCKBASED_COMPENSATION_Narrat

STOCK-BASED COMPENSATION - Narrative (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 29, 2015	Mar. 30, 2014
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	0.00%	0.00%
Unrecognized stock-based compensation, related to stock options	$1.80
Weighted average recognition period for stock-based compensation	2 years 7 months 6 days
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation, related to stock options	$2.80
Weighted average recognition period for stock-based compensation	3 years 1 month 6 days

STOCKBASED_COMPENSATION_Schedu

STOCK-BASED COMPENSATION - Schedule of Stock-Based Compensation (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 29, 2015	Mar. 30, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$516	$298
Cost of goods sold
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	34	2
Research, development and engineering
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	63	41
Selling, general and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	419	255
Stock options
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	245	247
Restricted stock units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	266	39
Employee stock purchase plan
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$5	$12

GEOGRAPHIC_AND_CUSTOMER_CONCEN2

GEOGRAPHIC AND CUSTOMER CONCENTRATION INFORMATION - Narrative (Details)	3 Months Ended		12 Months Ended
	Mar. 29, 2015	Mar. 30, 2014	Dec. 31, 2014
	segment	customer	customer
Concentration Risk [Line Items]
Number of operating segment	1
Customer Concentration Risk | Net Sales
Concentration Risk [Line Items]
Number of significant customers	2	2
Customer Concentration Risk | Net Sales | Net Sales, Major Customer A
Concentration Risk [Line Items]
Concentration percentage	63.00%	59.00%
Customer Concentration Risk | Net Sales | Net Sales, Major Customer B
Concentration Risk [Line Items]
Concentration percentage	13.00%	16.00%
Customer Concentration Risk | Net Accounts Receivable
Concentration Risk [Line Items]
Number of significant customers	2		1
Concentration percentage			74.00%
Customer Concentration Risk | Net Accounts Receivable | Net Accounts Receivable, Major Customer A
Concentration Risk [Line Items]
Concentration percentage	53.00%
Customer Concentration Risk | Net Accounts Receivable | Net Accounts Receivable, Major Customer B
Concentration Risk [Line Items]
Concentration percentage	19.00%

GEOGRAPHIC_AND_CUSTOMER_CONCEN3

GEOGRAPHIC AND CUSTOMER CONCENTRATION INFORMATION - Summary of Net Revenue by Geographic Area (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 29, 2015	Mar. 30, 2014
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, amount	$58,254	$43,198
Geographic Concentration Risk | Net Sales
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, percentage	100.30%	100.00%
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, amount	8,568	4,183
United States | Geographic Concentration Risk | Net Sales
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, percentage	15.00%	10.00%
South Korea
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, amount	33,998	10,259
South Korea | Geographic Concentration Risk | Net Sales
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, percentage	58.00%	24.00%
China
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, amount	3,599	13,081
China | Geographic Concentration Risk | Net Sales
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, percentage	6.00%	30.00%
Taiwan
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, amount	5,520	10,822
Taiwan | Geographic Concentration Risk | Net Sales
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, percentage	10.00%	25.00%
Other Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, amount	5,365	2,281
Other Asia | Geographic Concentration Risk | Net Sales
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, percentage	9.00%	5.00%
Europe and others
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, amount	$1,204	$2,572
Europe and others | Geographic Concentration Risk | Net Sales
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, percentage	2.00%	6.00%

GEOGRAPHIC_AND_CUSTOMER_CONCEN4

GEOGRAPHIC AND CUSTOMER CONCENTRATION INFORMATION - Summary of Geographic Information Relating to Property and Equipment (Details) (USD $)	Mar. 29, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	$9,248	$7,534
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	4,582	4,140
Germany
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	4,456	3,185
Others
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	$210	$209

INCOME_TAXES_Narrative_Details

INCOME TAXES - Narrative (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 29, 2015	Mar. 30, 2014
Income Tax Disclosure [Abstract]
Provision for income taxes	$521	$189

NET_INCOME_LOSS_PER_SHARE_Summ

NET INCOME (LOSS) PER SHARE - Summary of Computation of Net Income Per Share of Common Stock (Details) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 29, 2015	Mar. 30, 2014
Schedule of Earnings Per Share [Line Items]
Net income	$6,305	$2,465
Denominator:
Weighted-average shares outstanding - basic (in shares)	74,700	66,275
Weighted-average shares outstanding - diluted (in shares)	77,265	67,971
Basic (in usd per share)	$0.08	$0.04
Diluted (in usd per share)	$0.08	$0.04
Stock Options and Restricted Stock Units
Denominator:
Effect of dilutive stock options and restricted stock units (in shares)	2,565	1,696

NET_INCOME_LOSS_PER_SHARE_Narr

NET INCOME (LOSS) PER SHARE - Narrative (Details) (Stock Options and Restricted Stock Units)	3 Months Ended
In Millions, unless otherwise specified	Mar. 29, 2015	Mar. 30, 2014
Stock Options and Restricted Stock Units
Schedule of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from diluted net income per share (in shares)	0.7	1.9

SUBSEQUENT_EVENTS_Narrative_De

SUBSEQUENT EVENTS - Narrative (Details) (USD $)	Mar. 29, 2015	Dec. 31, 2014
Subsequent Events [Abstract]
Common stock, par value per share (in usd per share)	$0.00	$0.00