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                                                                    EXHIBIT 10.3



                               TENCOR INSTRUMENTS
                  1993 NONEMPLOYEE DIRECTORS STOCK OPTION PLAN


         1.      Purpose.

                 The purpose of this Plan is to offer Nonemployee Directors of
Tencor Instruments an opportunity to acquire a proprietary interest in the
success of the Company, or to increase such interest, by purchasing shares of
the Company's Common Stock.  This Plan provides for the grant of Options to
purchase Shares.  Options granted hereunder shall be "Nonstatutory Options,"
and shall not include "incentive stock options" intended to qualify for
treatment under Sections 421 and 422 of the Internal Revenue Code of 1986, as
amended.

         2.      Definitions.

                 As used herein, the following definitions shall apply:

                 (a)  "Administrator" shall mean the entity, either the
Board or the committee of the Board, responsible for administering this Plan,
as provided in Section 3.

                 (b)  "Affiliate" means a parent or subsidiary corporation as
defined in the applicable provisions (currently, Sections 424(e) and (f),
respectively) of the Code.

                 (c)  "Board" shall mean the Board of Directors of the
Company, as constituted from time to time.

                 (d)  "Code" shall mean the Internal Revenue Code of 1986,
as amended from time to time, and any successor statute.

                 (e)  "Company" shall mean Tencor Instruments, a California
corporation.

                 (f)  "Common Stock" shall mean the Common Stock of the
Company.

                 (g)  "Disability" means permanent and total disability as
determined by the Administrator in accordance with the standards set forth in
Section 22(e)(3) of the Code.

                 (h)  "Exchange Act" means the Securities Exchange Act of 1934,
as amended from time to time, and any successor statute.

                 (i)  "Expiration Date" shall mean the last day of the term
of an Option established under Section 6(c).

                 (j)  "Fair Market Value" means as of any given date (a)
the closing price of the Common Stock on the NASDAQ National Market System as
reported in the Wall Street Journal; or (b) if the Common Stock is no longer
quoted on the NASDAQ National Market System but is listed on an established
stock exchange or quoted on any other established interdealer quotation system,
the
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closing price for the Common Stock on such exchange or system, as reported in
the Wall Street Journal.

                 (k)  "Nonemployee Director" shall mean any person who is a
member of the Board but is not an employee of the Company or any Affiliate of
the Company and has not been an employee of the Company or any Affiliate of the
Company at any time during the preceding twelve months.  Service as a director
does not in itself constitute employment for purposes of this definition.

                 (l)  "Option" shall mean a stock option granted pursuant
to this Plan.  Each Option shall be a nonstatutory option not intended to
qualify as an incentive stock option within the meaning of Section 422 of the
Code.

                 (m)  "Option Agreement" shall mean the written agreement
described in Section 6 evidencing the grant of an Option to a Nonemployee
Director and containing the terms, conditions and restrictions pertaining to
such Option.

                 (n)  "Optionee" shall mean a Nonemployee Director who
holds an Option.

                 (o)  "Plan" shall mean this Tencor Instruments 1993
Nonemployee Directors Stock Option Plan, as it may be amended from time to
time.

                 (p)  "Section" unless the context clearly indicates
otherwise, shall refer to a Section of this Plan.

                 (q)  "Shares" shall mean the shares of Common Stock
subject to an Option granted under this Plan.

                 (r)  "Tax Date" means the date defined in Section 7(c).

                 (s)  "Termination" means, for purposes of the Plan, with
respect to an Optionee, that the Optionee has ceased to be, for any reason, a
director of the Company.

                 (t)  "Window Period" means any 10-day period beginning on the
third business day following the date of release for publication of the
Company's quarterly or annual summary statements of earnings or such other
period as is specified in Rule 16b-3(e) under the Exchange Act, as such rule
may be amended from time to time, or any successor to such rule.

         3.      Administration.

                 (a)  Administrator.  The Plan shall be administered by the
Board or, upon delegation by the Board, by a committee consisting of not less
than two directors (in either case, the "Administrator").  The Administrator
shall have no authority, discretion or power to select the Nonemployee
Directors who will




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receive Options hereunder or to set the number of shares to be covered by each
Option granted hereunder, the exercise price of such Option, the timing of the
grant of such Option or the period within which such Option may be exercised.
In connection with the administration of the Plan, the Administrator shall have
the powers possessed by the Board.  The Administrator may act only by a
majority of its members.  The Administrator may delegate administrative duties
to such employees of the Company as it deems proper, so long as such delegation
is not otherwise prohibited by Rule 16b-3 under the Exchange Act.  The Board at
any time may terminate the authority delegated to any committee of the Board
pursuant to this Section 3(a) and revest in the Board the administration of the
Plan.

                 (b)  Administrator Determinations Binding.  Subject to the
limitations set forth in Section 3(a), the Administrator may adopt, alter and
repeal administrative rules, guidelines and practices governing the Plan as it
from time to time shall deem advisable, may interpret the terms and provisions
of the Plan, any Option and any Option Agreement and may otherwise supervise
the administration of the Plan.  All decisions made by the Administrator under
the Plan shall be binding on all persons, including the Company and Optionees.
No member of the Administrator shall be liable for any action that he or she
has in good faith taken or failed to take with respect to this Plan or any
Option.

         4.      Eligibility.

                 Only Nonemployee Directors may receive Options under this
Plan.

         5.      Shares Subject to Plan.

                 (a)      Aggregate Number.  Subject to Section 9 (relating to
adjustments upon changes in Shares), the total number of shares of Common Stock
reserved and available for issuance pursuant to Options under this Plan shall
be 150,000 shares.  Such shares may consist, in whole or in part, of authorized
and unissued shares or shares reacquired in private transactions or open market
purchases, but all shares issued under the Plan regardless of source shall be
counted against the 150,000 share limitation.  If any Option terminates or
expires without being exercised in full, the shares issuable under such Option
shall again be available for issuance in connection with other Options.  If
shares of Common Stock issued pursuant to an Option are repurchased by the
Company, such Common Stock shall not again be available for issuance in
connection with Options.  To the extent the number of shares of Common Stock
issued pursuant to an Option is reduced to satisfy withholding tax obligations,
the number of shares withheld to satisfy the withholding tax obligations shall
not be available for later grant under the Plan.





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                 (b)      No Rights as a Shareholder.  An Optionee shall have
no rights as a shareholder with respect to any Shares covered by his or her
Option until the issuance (as evidenced by the appropriate entry on the books
of the Company or its duly authorized transfer agent) of a stock certificate
evidencing such Shares.  Subject to Section 9, no adjustment shall be made for
dividends (ordinary or extraordinary, whether in cash, securities or other
property), distributions, or other rights for which the record date is prior to
the date the certificate is issued.

         6.      Grant of Options.

                 (a)      Mandatory Initial Option Grants.  Subject to the
terms and conditions of this Plan, if any person who is not an officer or
employee of the Company and who has not previously been a member of the Board
is elected or appointed as a member of the Board, then on the effective date of
such appointment or election the Company shall grant to such new Nonemployee
Director an Option to purchase 5,000 Shares at an exercise price equal to the
Fair Market Value of such Shares on the date of such option grant.

                 (b)      Mandatory Annual Option Grants.  Subject to the terms
and conditions of this Plan, the Company shall grant to each Nonemployee
Director who was first elected or appointed to the Board more than twelve
months prior to the date of approval of the Plan by the Board an Option to
purchase 2,500 Shares at the Board meeting at which this Plan is approved at an
exercise price equal to the Fair Market Value of such Shares on the date of
such option grant.  Subject to the terms and conditions of this Plan, on the
date of the first meeting of the Board immediately following the annual meeting
of shareholders of the Company (even if held on the same day as the meeting of
shareholders) which is held more than twelve months after a Nonemployee
Director is first elected or appointed to the Board, commencing with the annual
meeting of shareholders held in 1994, the Company shall grant to each such
Nonemployee Director then in office an Option to purchase 2,500 Shares at an
exercise price equal to the Fair Market Value of such Shares on the date of
such option grant.

                 (c)      Terms; Vesting.  Subject to the other provisions of
this Plan, each Option granted pursuant to this Plan shall be for a term of ten
years.  Each Option granted under Section 6(a) shall become exercisable with
respect to one third of the number of Shares covered by such Option on the
first anniversary of the date such Option was granted and one thirty-sixth of
the number of shares covered by such Option each month thereafter, so that such
Option shall be fully exercisable on the third anniversary of the date such
Option was granted.  Each Option granted under Section 6(b) shall become
exercisable with respect to one thirty-sixth of the number of shares covered by
such Option each month after the date of grant, so that such Option shall be
fully





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exercisable on the third anniversary of the date such Option was granted.

                 (d)      Limitation on Other Grants.  The Administrator shall
have no discretion to grant Options under this Plan other than as set forth in
Sections 6(a) and 6(b).

                 (e)      Option Agreement.  As soon as practicable after the
grant of an Option, the Optionee and the Company shall enter into a written
Option Agreement which specifies the date of grant, the number of Shares, the
option price, and the other terms and conditions applicable to the Option.

                 (f)      Transferability.  No Option shall be transferable
otherwise than by will or the laws of descent and distribution, and an Option
shall be exercisable during the Optionee's lifetime only by the Optionee.

                 (g)      Limits on Exercise.  Subject to the other provisions
of this Plan, an Option shall be exercisable in such amounts as are specified
in the Option Agreement.

                 (h)      Exercise Procedures.  To the extent the right to
purchase Shares has accrued, Options may be exercised, in whole or in part,
from time to time, by written notice from the Optionee to the Company stating
the number of Shares being purchased, accompanied by payment of the exercise
price for the Shares, and other applicable amounts, as provided in Section 7.

                 (i)  Termination.  In the event of Termination, Options held
at the date of Termination (and only to the extent then exercisable) may be
exercised in whole or in part at any time within three months after the date of
Termination (but in no event after the expiration date of the Option), but not
thereafter.  Notwithstanding the foregoing, if Termination is due to retirement
or to death or Disability or if the Optionee dies within three months after
Termination, Options held at the date of Termination (and only to the extent
then exercisable) may be exercised in whole or in part by the Optionee in the
case of retirement or Disability, by the participant's guardian or legal
representative or by the person to whom the Option is transferred by will or
the laws of descent and distribution, at any time within 18 months from the
date of Termination (but in no event after the expiration of the Option).

         7.      Payment and Taxes upon Exercise of Options.

                 (a)      Purchase Price.  The purchase price of Shares issued
under this Plan shall be paid in full at the time an Option is exercised.

                 (b)  Delivery of Purchase Price.  Optionees may make all or
any portion of any payment due to the Company





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                          (i)  upon exercise of an Option, or

                          (ii)  with respect to federal, state, local or
foreign tax payable in connection with the exercise of an Option,

by delivery of (x) cash, (y) check, or (z) a promissory note of the Optionee or
shares of Common Stock so long as, if applicable, such property constitutes
valid consideration for the Common Stock under, and otherwise complies with,
applicable law.  No promissory note under the Plan shall have a term (including
extensions) of more than five years or shall be of a principal amount exceeding
90% of the purchase price paid by the borrower.  Exercise of an Option may be
made pursuant to a "cashless exercise/sale" procedure pursuant to which funds
to pay for exercise of the Option are delivered to the Company by a broker upon
receipt of stock certificates from the Company, or pursuant to which Optionees
obtain margin loans from brokers to fund the exercise of the Option.

                 (c)  Tax Withholding.  The Optionee shall pay to the Company
in cash, promptly upon exercise of an Option or, if later, the date that the
amount of such obligations becomes determinable (in either case, the "Tax
Date"), all applicable federal, state, local and foreign withholding taxes that
the Administrator, in its discretion, determines to result upon exercise of an
Option or from a transfer or other disposition of shares of Common Stock
acquired upon exercise of an Option or otherwise related to an Option or shares
of Common Stock acquired in connection with an Option.

                 A person who has exercised an Option may make an election (i)
to deliver to the Company a promissory note of the Optionee on the terms set
forth in Section 7(b), (ii) to tender to the Company previously-owned shares of
Common Stock held for at least six months, or (iii) to have shares of Common
Stock to be obtained upon exercise of the Option withheld by the Company on
behalf of the Optionee, to pay the amount of tax that the Administrator, in its
discretion, determines to be required to be withheld by the Company.  Any
election pursuant to clause (iii) above by a Optionee subject to Section 16 of
the Exchange Act shall be subject to the following limitations:  (1) such
election must be made at least six months before the Tax Date and shall be
irrevocable; or (2) such election must be made in (or made earlier to take
effect in) any Window Period (and the withholding of the shares of Common Stock
shall take place during such Window Period) and shall be subject to approval by
the Board, which approval may be given any time after such election has been
made, and the Option must be held at least six months prior to the Tax Date;
provided, that, the election referenced in clause (2) above may not be made
unless (A) such election is consistent with Rule 16b-3(c)(2)(ii) under the
Exchange Act, and (B) the Company has been subject to the reporting
requirements of Section 13(a) of the Exchange Act for at least one year and has
filed all reports





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and statements required to be filed pursuant to that section for that year.
The right to so withhold shares of Common Stock shall relate separately to each
Option.

         Any shares tendered to or withheld by the Company will be valued at
Fair Market Value on such date.  The value of the shares of Common Stock
tendered or withheld may not exceed the required federal, state, local and
foreign withholding tax obligations as computed by the Company.

         8.      Use of Proceeds.

                 Proceeds from the sale of Shares pursuant to this Plan shall
be used for general corporate purposes.

         9.      Adjustment of Shares.

                 (a)      Adjustments.  Subject to Section 9(d), in the event
of any merger, reorganization, consolidation, recapitalization, stock dividend,
stock split or other change in corporate structure affecting the Common Stock,
such substitution or adjustments shall be made in the aggregate number and kind
of shares of Stock reserved for issuance under the Plan and in the number, kind
and exercise price of shares subject to outstanding Options, as may be
determined to be appropriate by the Administrator, in its sole discretion;
provided, however, that the number of shares subject to any Option shall always
be a whole number.

                 (b)  Definition of "Change in Control".  For purposes of
Section 9(c), a "Change in Control" means the occurrence of any one of the
following:

                          (i)  Any "person", as such term is used in Sections
13(d) and 14(d) of the Exchange Act (other than the Company, an Affiliate, or a
Company employee benefit plan, including any trustee of such plan acting as
trustee) is or becomes the "beneficial owner" (as defined in Rule 13d-3 under
the Exchange Act), directly or indirectly, of securities of the Company
representing 20% or more of the combined voting power of the Company's then
outstanding securities;

                          (ii)  the solicitation of proxies (within the meaning
of Rule 14a-1(k) under the Exchange Act and any successor rule) with respect to
the election of any director of the Company where such solicitation is for any
candidate who is not a candidate proposed by a majority of the Board in office
prior to the time of such election; or

                          (iii)  the dissolution or liquidation (partial or
total) of the Company or a sale of assets involving 30% or more of the assets
of the Company, or any merger or reorganization of the Company (other than a
merger effected before May 31, 1994),





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whether or not another entity is the survivor, or other transaction pursuant to
which the holders, as a group, of all of the shares of the Company outstanding
prior to the transaction hold, as a group, less than 70% of the shares of the
Company outstanding after the transaction.

                 (c)  Impact of Event.  In the event of a "Change in Control"
as defined in Section 9(b), any Options outstanding as of the date such Change
in Control is determined to have occurred and not then exercisable and vested
shall become fully exercisable and vested.

         10.     No Right to Directorship.

                 Neither, this Plan nor any Option granted hereunder shall
confer upon any Optionee any right with respect to continuation of the
Optionee's membership on the Board or shall interfere in any way with
provisions in the Company's Articles of Incorporation and By-Laws relating to
the election, appointment, terms of office, and removal of members of the
Board.

         11.     Legal Requirements.

                 The Company shall not be obligated to offer or sell any Shares
upon exercise of any Option unless the Shares are at that time effectively
registered or exempt from registration under the federal securities laws and
the offer and sale of the Shares are otherwise in compliance with all
applicable securities laws and the regulations of any stock exchange on which
the Company's securities may then be listed.  The Company shall have no
obligation to register the securities covered by this Plan under the federal
securities laws or take any other steps as may be necessary to enable the
securities covered by this Plan to be offered and sold under federal or other
securities laws.  Upon exercising all or any portion of an Option, an Optionee
may be required to furnish representations or undertakings deemed appropriate
by the Company to enable the offer and sale of the Shares or subsequent
transfers of any interest in the Shares to comply with applicable securities
laws.  Certificates evidencing Shares acquired upon exercise of Options shall
bear any legend required by, or useful for purposes of compliance with,
applicable securities laws, this Plan or the Option Agreements.

         12.     Duration and Amendments.

                 (a)      Duration.  This Plan shall become effective upon
adoption by the Board provided, however, that no Option shall be exercisable
unless and until written consent of the shareholders of the Company, or
approval of shareholders of the Company voting at a validly called
shareholders' meeting, is obtained within 12 months after adoption by the
Board. If such shareholder approval is not obtained within such time, Options
granted hereunder shall





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terminate and be of no force and effect from and after expiration of such
12-month period.

                 (b)      Amendment and Termination.  The Board may amend,
alter or discontinue the Plan or any Option, but no amendment, alteration or
discontinuance shall be made which would impair the rights of an Optionee under
an outstanding Option without the Optionee's consent.  In addition, the Board
may not amend or alter the Plan without the approval of shareholders of the
Company entitled to vote at a duly held shareholders' meeting or by an action
by written consent and, if at a meeting, a quorum of the voting power of the
Company is represented in person or by proxy, where such amendment or
alteration would, except as expressly provided in the Plan, increase the total
number of shares reserved for issuance pursuant to Options under the Plan or in
such other circumstances as the Board deems appropriate to comply with Rule
16b- 3 under the Exchange Act or otherwise.  Notwithstanding any other
provision of this Section 12(b), the provisions of the Plan governing (A) who
is granted Options, (B) the number of Shares to be covered by each Option, (C)
the exercise price of each Option, (D) the timing of the grant of each Option,
or (E) the period within which each Option may be exercised, shall not be
amended more than once every six months, other than to comport with changes in
the Code or the rules thereunder or the Employee Retirement Income Security Act
of 1974, as amended, or the rules thereunder.

                 (c)      Effect of Amendment or Termination.  No Shares shall
be issued or sold under this Plan after the termination hereof, except upon
exercise of an Option granted before termination.  Termination or amendment of
this Plan shall not affect any Shares previously issued and sold or any Option
previously granted under this Plan.

         13.  Rule 16b-3.

                 With respect to persons subject to Section 16 of the Exchange
Act, transactions under this Plan are intended to comply with the applicable
conditions of Rule 16b-3 under the Exchange Act.  To the extent any provision
of this Plan or action by the Administrator fails to so comply, it shall be
adjusted to comply with Rule 16b-3, to the extent permitted by law and deemed
advisable by the Administrator.  It shall be the responsibility of persons
subject to Section 16 of the Exchange Act, not of the Company or the
Administrator, to comply with the requirements of Section 16 of the Exchange
Act; and neither the Company nor the Administrator shall be liable if this Plan
or any transaction under this Plan fails to comply with the applicable
conditions of Rule 16b-3, or if any such person incurs any liability under
Section 16 of the Exchange Act.





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Adopted by the Board of Directors: May 10, 1993

Amendment approved by the Board of Directors: February 14, 1994

Plan, as amended, approved by the shareholders: May 4, 1994

Two-for-one stock split with a record date of May 31, 1995 and a distribution
date of June 21, 1995, which increased the number of shares from 50,000 to
100,000, was approved by the Board of Directors on May 15, 1995.

Amendment to Plan increasing the number of shares to 150,000 approved by the
Board of Directors on February 12, 1996.

Amendment to Plan increasing the number of shares to 150,000 approved by the
Shareholders on May 13, 1996.





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