EXHIBIT 10.21
 
                             EMPLOYMENT AGREEMENT
 
  This Employment Agreement (this "Agreement"), dated November 15, 1996, is
entered into by and between Nigel Wheeler ("Executive") and Plasma & Materials
Technologies, Inc., a California corporation ("Employer").
 
                                  WITNESSETH:
 
  WHEREAS, concurrently herewith, Employer will acquire all of the outstanding
shares of Electrotech Limited and Electrotech Equipments Limited, companies
organized under the laws of England and in the business of manufacturing and
selling semiconductor capital equipment (the "Business");
 
  WHEREAS, Executive has been employed as the Chief Executive Officer of
Electrotech Limited and Electrotech Equipments Limited and has skills and
experience in the Business and the technology associated therewith; and
 
  WHEREAS, Employer desires to obtain Executive's services for the conduct of
its Business, and Executive desires to be employed in such Business by and for
Employer.
 
  NOW, THEREFORE, in consideration of the premises and the mutual covenants
herein set forth, the parties hereto agree as follows:
 
  1. Definitions. As used in this Agreement, the following terms shall have
the meanings set forth below.
 
    (a) "Affiliate" means any corporation, partnership, limited liability
  company or other person or entity that directly, or indirectly through one
  or more intermediaries, controls or is controlled by, or is under common
  control with, the person or entity specified. For the purposes hereof,
  "control" means both the right to direct or cause the direction of the
  management and policies of an entity, whether through ownership of voting
  rights, by contract or otherwise, including with limitation the right to
  sell or cause the sale of all or substantially all of the assets of such
  entity.
 
    (b) "Board" means the Board of Directors of Employer.
 
    (c) "Disability" or "Disabled" has the meaning set forth in Section 10(b)
  hereof.
 
    (d) "Effective Date of Termination" has the meaning set forth in Section
  10(f) hereof.
 
    (e) "Termination For Cause" means the termination by Employer of
  Executive's employment because he has been convicted of a felony or been
  adjudged by a court of competent jurisdiction to have defrauded Employer,
  any Affiliate of Employer or any customer of Employer.
 
    (f) "Termination For Good Reason" means a termination by Executive of his
  employment with Employer based on (i) a material diminution of Executive's
  duties as President and Chief Operating Officer, (ii) the imposition by the
  Board of a requirement that Executive report to persons other than the
  Board, the Chairman or the Chief Executive Officer, (iii) the breach by
  Employer of any of its material obligations under this Agreement or (iv)
  Employer ceasing to be engaged in the Business or in any business that is
  substantially similar to the Business.
 
    (g) "Termination Without Cause" means a termination by Employer of
  Executive's employment that is not a Termination For Cause or a termination
  resulting from Executive's death or Disability.
 
    (h) "Termination Without Good Reason" means a termination by Executive of
  his employment with Employer that is not a Termination For Good Reason or a
  termination resulting from Executive's death or Disability.
 
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  2. Employment. Employer hereby employs Executive as an executive officer and
Executive hereby accepts such employment upon the terms and conditions
hereinafter set forth.
 
  3. Duties.
 
    (a) Executive shall perform his services as President and Chief Operating
  Officer, under the supervision of the Chairman and the Chief Executive
  Officer of Employer and within the framework of the policies and objectives
  of Employer. In such capacity, Executive (i) shall exercise general day-to-
  day supervisory responsibility and operational and management authority
  over Employer and its officers and executives and all of its Affiliates and
  their respective officers and executives, (ii) shall provide advice and
  input to members of Employer's Board and shall, at their request, attend
  all meetings of the Board for that purpose, and (iii) shall perform such
  other duties as may be assigned to him from time to time by the Board.
 
    (b) Executive shall devote his entire business time, attention and
  energies to the performance of his duties and functions under this
  Agreement and shall not during the term of his employment hereunder be
  engaged in any other substantial business activity for gain, profit or
  other pecuniary advantage. Executive shall faithfully, loyally and
  diligently perform his assigned duties and functions and shall not engage
  in any activities whatsoever which conflict with the objectives of
  Employer's Business during the term of his employment hereunder.
 
    (c) Employer shall furnish Executive with such facilities at the
  corporate offices of Electrotech Limited and services as are suitable to
  his position and adequate for the performance of his duties and functions
  hereunder. It is understood that Executive's "home base" location shall be
  at Ringland Way, Newport, Gwent NP62TA.
 
  4. Director. During the term of this Agreement, Executive shall be nominated
to serve as a director of the Board of Employer.
 
  5. Term. The term of this Agreement shall commence on the date hereof and
shall continue until _________ , 1999 (the "Initial Term"), and thereafter shall
continue for additional one-year periods unless and until such time as either
party hereto provides written notice to the other thirty (30) days prior to
the end of the third year of the Initial Term or prior to the end of any such
additional one-year period (such additional one-year periods, together with
the Initial Term, the "Employment Term"). Upon any termination of Executive's
employment hereunder (other than a Termination Without Good Reason or a
Termination for Cause), Executive shall be retained as a consultant to
Employer until all of the stock options described in Section 6(c), and any
other stock options which may have been granted to Executive, have fully
vested, upon acceleration or otherwise.
 
  6. Compensation. Employer shall pay to Executive, as compensation for the
services agreed to be rendered by Executive hereunder, the following:
 
    (a) Base Salary. During the Employment Term, Employer shall pay to
  Executive a salary of (pounds) 163,000 per annum payable in British pounds
  sterling; provided, that the amount of such base salary shall be reviewed
  and may be adjusted by Employer annually during the Employment Term in
  light of the conditions then existing and the services then being rendered
  by Executive, in which case Executive's base salary shall be such higher
  amount as may be determined by Employer (such annual base salary, as in
  effect from time to time, being referred to herein as the "Base Salary").
  The Base Salary shall be payable monthly, less appropriate deductions for
  federal, state and local income taxes, FICA contributions and any other
  deductions required by law or authorized by Executive.
  
    (b) Annual Performance Bonus. In addition to the Base Salary, Executive
  shall be eligible to receive an annual performance bonus (the "Annual
  Bonus") for each year of service (or any part thereof in the event of
  termination of Executive's employment hereunder (other than a Termination
  Without Good Reason or a Termination for Cause), in which case any Annual
  Bonus shall be prorated for such partial year) during the Employment Term
  (each such year or any partial such year referred to as an "Annual Bonus
  Period"),
 
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  to the maximum extent of eligibility permitted to executive officers, or if
  no such bonus is permitted, in such amount, if any, as may be determined by
  the Board in its discretion. Each Annual Bonus shall be payable in British
  pounds sterling at the exchange rate prevailing at the date of payment
  which shall be in accordance with Employer's normal annual bonus payment
  schedule, less appropriate deductions for federal, state, and local income
  taxes, FICA contributions and any other deductions required by law or
  authorized by Executive.
 
    (c) Options. Concurrently herewith, the Compensation Committee of the
  Board of Employer shall grant to Executive, pursuant to Employer's 1991
  Stock Option Plan, options to acquire 200,000 shares of Employer's common
  stock at an exercise price equal to the fair market value of the underlying
  shares of common stock on the date of such grant, 25% of which shall vest
  on each anniversary of the date of grant over a period of four years (the
  "Options), subject to Executive's continuous employment or consultancy with
  Employer pursuant hereto.
 
    (d) Payment of Additional Amount. Employer shall pay to Executive, for so
  long as Executive is not a resident of the United States, as additional
  payments, such amounts as may be necessary in order that every net payment
  of Executive's salary, bonus or other payment, after deducting or
  withholding for or on account of any present or future tax, assessment or
  other governmental charge imposed upon, or as a result of, such payment by
  the government of the United States or any state thereof or any political
  subdivision or taxing authority of or in the United States, will not be
  less than (x) the gross amount provided for herein, as may be adjusted by
  the Board of Directors pursuant hereto, then due and payable minus (y) the
  amount of income taxes payable by Executive or required to be deducted or
  withheld for or on account of any present or future tax, assessment or
  other governmental charge.
 
  7. Benefits. During the Employment Term, Executive shall receive benefits,
in England, including, but not limited to (a) life insurance equal to four
times Executive's Base Salary, (b) medical insurance for Executive and his
family, (c) home telephone for business and private use, (d) company car for
business and private use, including fuel, (e) continuation of pension plan
benefits, including employer contributions based on actuarials, (f) business
class travel, and (g) all benefits offered to other executive officers of the
Employer to the maximum extent so offered.
 
  8. Expenses. During the Employment Term, Employer shall reimburse Executive
for all reasonable travel, entertainment and other expenses incurred or paid
by Executive in performing his duties and functions hereunder, upon
Executive's submission of reasonable documentation thereof.
 
  9. Vacations. In addition to such holidays, sick leave and personal time off
as is allowed under the policies of Employer to management generally,
Executive shall be entitled during each twelve-month period during the
Employment Term to twenty-five (25) days of vacation and all statutory bank
holidays of England, with full pay. The duration of such vacations and the
time or times when they shall be taken will be determined by Executive in
consultation with Employer.
 
  10. Termination.
 
    (a) Death. The Employment Term will terminate automatically in the event
  of Executive's death. Upon such termination, Executive will be entitled to
  receive the payments prescribed by subsection 10(c)(iii).
 
    (b) Disability. If Executive becomes Disabled, Employer may elect to give
  written notice of termination to Executive, which notice will specify the
  date of termination. Upon such termination, Executive will be released from
  any duties and obligations hereunder (except as set forth in Section 11)
  and Executive will be entitled to receive the payments prescribed by
  subsection 10(c)(i). "Disabled" as used in this Agreement means the
  inability of Executive substantially to perform his duties for a period of
  180 consecutive days or for a total of 180 days or more in any 360-day
  period as a result of a physical or mental illness, all as determined in
  good faith and on a reasonable basis by the Board. The Board will be deemed
  to have acted in good faith only if it acts in reliance on the advice of at
  least two physicians reasonably believed by the Board to be competent in
  such matters.
 
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    (c) Termination For Cause or Without Good Reason. The Employment Term may
  be terminated by a Termination For Cause or a Termination Without Good
  Reason. Upon either such termination, Executive will be released from any
  duties and obligations under this Agreement (except as set forth in Section
  11) and Executive will be entitled to receive the payments prescribed by
  subsection 10(e)(ii). Executive will not be entitled to any other payment
  in the event of a Termination For Cause or a Termination Without Good
  Reason other than any payment prescribed by Section 10(c)(ii) relating to
  the period before the Effective Date of Termination.
 
    (d) Termination Without Cause or For Good Reason. The Employment Term
  will be terminated by a Termination Without Cause or a Termination For Good
  Reason. Upon either such termination, Executive will be released from any
  duties under this Agreement (except as set forth in Section 11) and
  Executive will be entitled to receive the payments prescribed by subsection
  (10(e)(i).
 
    (e) Payment Upon Termination. If the Employment Term is terminated before
  the third anniversary of the date of this Agreement, in addition to any
  rights Executive may have with respect to payments, if any, pursuant to
  Section 6, Employer will pay to Executive the following compensation which
  when paid will be deemed to be paid in final settlement of any claims in
  connection with such termination Executive may have against Employer or any
  Affiliate of Employer, and after such payments are made, Employer and its
  Affiliates will have no liability or obligation of any kind to Executive in
  connection with such termination:
 
      (i) Payment Upon Termination Without Cause or For Good Reason. If a
    Termination Without Cause or a Termination For Good Reason has
    occurred, or if Executive becomes Disabled, Executive will be entitled
    to receive his Base Salary (at the rate of effect at the Effective Date
    of Termination) through the remainder of the Employment Term (which,
    for purposes of this Section 10(e)(i), shall not be less than one
    year), without setoff or reduction in respect of such amounts, if any,
    earned by Executive from other employment after the Effective Date of
    Termination either, at Executive's election, in a lump sum payment or
    in the same manner as paid prior to the Effective Date of Termination
    and Executive shall receive all the benefits to which he is entitled
    pursuant to clauses (a), (b) and (e) of Section 7 through the remainder
    of the Employment Term.
 
      (ii) Payment Upon Termination For Cause or Without Good Reason. If a
    Termination For Cause or a Termination Without Good Reason has
    occurred, Employer will pay to Executive his Base Salary (as in effect
    on the Effective Date of Termination) and other benefits, including
    accrued vacation pay, (without setoff or reduction in respect of such
    amounts) to which Executive is entitled pursuant to this Agreement
    through the Effective Date of Termination.
 
      (iii) Payment Upon Termination in the Event of Death. In the case of
    a termination of this Agreement upon Executive's death, Executive's
    estate shall be entitled to receive his Base Salary (at the rate in
    effect on the date of death) through the end of the month in which the
    Effective Date of Termination occurs and other benefits including those
    specified in Section 7 hereof through the end of the month in which the
    Effective Date of Termination occurs and accrued vacation pay (all
    without setoff or reduction in respect of such amounts).
 
    (f) Effective Date of Termination. The "Effective Date of Termination" of
  Executive's employment will be: (i) in the case of a Termination Without
  Cause, on the date specified in a notice given by Employer to Executive or,
  if no date is specified, on the date such notice is given; (ii) in the case
  of a Termination Without Good Reason, on the date specified in a notice
  given by Executive to Employer or, if no date is specified, on the date
  such notice is given; (iii) in the case of a Termination For Good Reason,
  the date notice of termination is given by Executive; or (iv) in the case
  of a Termination For Cause, the date notice of termination is given by
  Employer; (v) in the case of Executive's death, the date of death; and (vi)
  in case Executive is determined to be Disabled, the date the Board
  determines that Executive is Disabled.
 
  11. Confidentiality. During the Employment Term, Executive will not use for
his own advantage or disclose any proprietary or confidential information
relating to the business operations or properties of Employer,
 
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any Affiliate of Employer or any of their respective customers, suppliers,
landlords, licensors or licensees. Upon the expiration or termination of the
Employment Term, Executive will surrender and deliver to Employer all
documents and information of every kind relating to or connected with Employer
and its Affiliates and their respective businesses, customers, suppliers,
landlord, licensors and licensees. The foregoing confidential information
provisions shall not apply to information which: (i) is or becomes publicly
known through no wrongful act of the Executive; (ii) is rightfully received
from any third party without restriction and without breach by Executive of
this Employment Agreement; or (iii) is independently developed by Executive
after the term of his employment hereunder or is independently developed by a
competitor of Employer at any time. The provisions of this Section 11 shall
survive the expiration and/or termination of this Employment Agreement for a
period of two years from the Effective Date of Termination.
 
  12. Non-Compete. During the Noncompetition Term (as defined below) Executive
will not directly or indirectly engage in competition with Employer by being
associated in any capacity (whether as employee, owner, consultant, agent or
otherwise) with any person or entity that sells or offers to sell any products
or services which are in the same line of business as the Business and which
directly compete in any area in the world where the Employer's products or
services are offered or sold by Employer. The foregoing sentence shall not
preclude the ownership by Executive of 10% or less of any class of security of
any issuer which is registered pursuant to the Securities Exchange Act of
1934, as amended, or which is listed on the London Stock Exchange. As used
herein, "Noncompetition Term" means the period of Executive's employment with
Employer and for such period after an Effective Date of Termination during
which Executive continues to receive any payments equal to his Base Salary
pursuant to subsection 10(e)(i) above.
 
  13. Arbitration. Any dispute or controversy arising out of or relating to
this Agreement or any claimed breach hereof shall be settled, at the request
of either party, by an arbitration proceeding conducted in accordance with the
rules of the American Arbitration Association ("AAA"), with the award
determined to be appropriate by the arbitrator therein to be final, non-
appealable and binding on the parties hereto, and with judgment upon such
award as is rendered in any such arbitration proceeding available for entry
and enforcement in any court having jurisdiction of the parties hereto. The
arbitrator shall be an impartial arbitrator qualified to serve in accordance
with the rules of the AAA and shall be reasonably acceptable to each of the
Employer and the Executive. If no such acceptable arbitrator is so appointed
within fifteen (15) days after the initial request for arbitration of such
disputed matter, each of the parties promptly shall designate a person
qualified to serve as an arbitrator in accordance with the rules of the AAA,
and the two persons so designated promptly shall select the arbitrator from
among those persons qualified to serve in accordance with the rules of the
AAA. The arbitration shall be held in the State of California in the United
States at the time of the initiation of any such proceedings, or in such other
place as may be agreed upon at the time by the parties. The expenses of the
arbitration proceeding shall be borne by Employer.
 
  14. Indemnification.
 
    (a) Employer shall indemnify Executive to the fullest extent permitted by
  the Articles of Incorporation and Bylaws of Employer as in effect on the
  date hereof (or if such Articles of Incorporation or Bylaws are amended to
  broaden such indemnification, then such broadened indemnification terms
  shall apply) against all costs, expenses, liabilities and losses
  (including, without limitation, attorneys' fees, judgments, penalties and
  amounts paid in settlement) reasonably incurred by Executive in connection
  with any action, suit or proceeding, whether civil, criminal,
  administrative or investigative in which Executive is made, or is
  threatened to be made, a party to or a witness in such action, suit or
  proceeding by reason of the fact that he is or was an officer, director,
  consultant, agent or Executive of the Employer or of any of Employer's
  Affiliates or is or was serving as an officer, consultant, director,
  member, Executive, trustee, agent or fiduciary of any other entity at the
  request of the Employer (a "Proceeding"). Employer shall maintain policies
  for insurance coverage of Executive to the fullest extent available to any
  other director or officer of Employer, which shall include director and
  officer insurance and insurance coverage relating to acts of Employer prior
  to the commencement of Executive's employment hereunder. Employer shall
  enter into an
 
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  indemnification agreement with Executive to the same extent Employer has
  entered into such agreements with other executive officers of Employer.
 
    (b) The indemnification provided to Executive hereunder is in addition
  to, and not in lieu of, any additional indemnification to which he may be
  entitled pursuant to Employer's Articles of Incorporation or Bylaws, any
  insurance maintained by Employer from time to time providing coverage to
  Executive and other officers and directors of Employer, or any separate
  written agreement with Executive. The provisions of this Section 14 shall
  survive any termination of this Agreement.
 
  15. Amendment and Modification. This Agreement contains the entire agreement
between the parties with respect to the subject matter hereof. Such to
applicable law and upon the consent of the Board of Employer, this Agreement
may be amended, modified and supplemented by written agreement of Employer and
Executive with respect to any of the terms contained herein.
 
  16. Waiver of Compliance. Any failure of either party to comply with any
obligation, covenant, agreement or condition on its part contained herein may
be expressly waived in writing by the other party, but such waiver or failure
to insist upon strict compliance shall not operate as a waiver of, or estoppel
with respect to, any subsequent or other failure. Whenever this Agreement
requires or permits consent by or on behalf of any party, such consent shall
be given in writing.
 
  17. Notices. All notices, requests, demands and other communications
required or permitted hereunder shall be in writing and shall be deemed to
have been duly given if delivered by hand, sent by registered or certified
U.S. Mail, postage prepaid, commercial overnight courier service or
transmitted by facsimile and shall be deemed served or delivered to the
addressee at the address for such notice specified below when hand delivered,
upon confirmation of sending when sent by facsimile, on the second day after
being sent when sent by overnight delivery or ten (10) days after having been
mailed, certified or registered mail with postage prepaid:
 
  If to Employer:                        If to Executive:
 
 
  Plasma & Materials Technologies, Inc.  Nigel Wheeler
  9255 Deering Avenue                    Ringland Way
  Chatsworth, CA 91311                   Newport, Gwent NP62TA
  Attention: Chief Executive Officer     Facsimile: 011-44-1-633-414-040
  Facsimile: (818) 886-8756
 
or, in the case of either such party, to such substitute address as such party
may designate from time to time for purposes of notices to be given to such
party hereunder, which substitute address shall be designated as such in a
written notice given to the other party addressed as aforesaid.
 
  18. Assignment. This Agreement shall inure to the benefit of Executive and
Employer and be binding upon the successors and general assigns of Employer.
This Agreement shall not be assignable without consent of the parties hereto
which consent may be given or withheld in the sole discretion of the parties
hereto.
 
  19. Enforceability. In the event it is determined that this Agreement is
unenforceable in any respect, it is the mutual intent of the parties that it
be construed to apply and be enforceable to the maximum extent permitted by
applicable law.
 
  20. Applicable Law. This Agreement shall be construed and enforced in
accordance with the laws applicable to contracts executed, delivered and fully
to be performed in the State of California.
 
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  IN WITNESS WHEREOF, the parties have executed this Agreement to be effective
on and as of the day and year first above written.
 
                                          EMPLOYER:
 
                                          PLASMA & MATERIALS TECHNOLOGIES,
                                           INC.
 
                                          By: /s/ Gregor A. Campbell
                                              ----------------------------------
                                             Name: Gregor A. Campbell
                                             Title: President and Chief 
                                                    Financial Officer
 
                                          EXECUTIVE:
 
                                          /s/ Nigel Wheeler
                                          -------------------------------------
                                              Nigel Wheeler
 
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