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                                                                    EXHIBIT 10.2

                                  TENCOR INSTRUMENTS
                         NONSTATUTORY STOCK OPTION AGREEMENT

             (A)  Name of Optionee: ___________________
             (B)  Grant Date: _________________________
             (C)  Number of Shares: ___________________
             (D)  Exercise Price: _____________________
             (E)  Effective Date: _____________________
             (F)  Percentage to Vest at end Year One: ___%
             (G)  Percentage to Vest Monthly/Annually After Year One: ___%

     THIS NONSTATUTORY STOCK OPTION AGREEMENT (the "Agreement") is made and 
entered into as of the date set forth in Item E above (the "Effective Date") 
between Tencor Instruments, a California corporation (the "Company"), and the 
person named in Item A above ("Optionee"). This option will not be treated as 
an "incentive stock option" within the meaning of Section 422 of the Internal 
Revenue Code.

     1.  GRANT. The Company hereby grants to Optionee pursuant to the 
Company's 1993 Amended and Restated Equity Incentive Plan (the "Plan"), the 
terms and conditions of which are incorporated herein by this reference, an 
option (the "Option") to purchase the number of shares (the "Option Shares") 
of the Company's common stock listed in Item C above on the terms and 
conditions set forth herein and in the Plan.

     2.  VESTING OF OPTION SHARES. The vesting base date (the "Vesting Base 
Date") shall be the same date as the grant date set forth in Item B above; 
the Option Shares shall vest on the first anniversary of the Vesting Base 
Date at the rate specified in Item F above; the Option Shares shall vest at 
the end of each full period thereafter at the rate specified in Item G above.

     3.  EXERCISE OF THE OPTION. This Option may be exercised in whole or 
part at any time. The exercise price shall be the price set forth in Item D 
above (the "Exercise Price"). Optionee hereby agrees that in the event that 
the Company deems it necessary or advisable in the exercise of its 
discretion, the issuance of Option Shares may be conditioned upon certain 
representations and acknowledgments by the person exercising the Option.

         a.  EXERCISE BEFORE VESTING. The Optionee may exercise the Option 
before vesting of the Option Shares by delivering to the Company: (i) the 
Exercise Price, (ii) an executed copy of the Notice of Exercise attached 
hereto as Exhibit 1, and (iii) an executed copy of the Acknowledgment and 
Statement of Decision Regarding Election attached hereto as Exhibit 2. Share 
certificates representing Option Shares purchased before vesting shall be 
held in escrow and released to the Optionee upon vesting, or at the Company's 
sole discretion, Option Shares purchased before vesting may be issued in book 
entry form without certification. The Company shall instruct the person 
maintaining the book entry system that such Option Shares shall not be 
available for transfer until such Option Shares are vested or the Company's 
right of repurchase (as provided in Section 4 below) has otherwise 
terminated. As a condition to exercising the Option before vesting of the 
Option Shares, the Optionee shall execute such documents as are reasonably 
necessary to carry out the intent of this Section, including

                                      -1-

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execution of an escrow agreement, the terms and conditions of which shall be 
determined by the Company at its sole discretion.

         b.  EXERCISE AFTER VESTING. The Optionee may exercise the Option 
after vesting of the Option Shares by delivering to the Company: (i) the 
Exercise Price, and (ii) an executed copy of the Notice of Exercise attached 
hereto as Exhibit 1.

     4.  RIGHT OF REPURCHASE. The Company shall have a right to repurchase 
(the "Right of Repurchase"), at the price paid by the Optionee, any Option 
Shares that have not vested. The Right of Repurchase shall terminate upon the 
later of: (i) 45 days after the date on which the Optionee ceases to be 
employed by, or a consultant to, the Company, or (ii) 30 days after the 
Option is exercised. Upon exercise of the Right of Repurchase, the Optionee 
shall endorse and deliver to the Company the stock certificates, if any, 
representing the Option Shares being repurchased and the Company shall pay 
the Optionee the repurchase price. Upon receipt of payment from the Company, 
the Optionee shall have no rights whatsoever in any Option Shares repurchased 
by the Company. Option Shares subject to the Right of Repurchase shall not be 
assigned, pledged, transferred, hypothecated or otherwise disposed of by the 
Optionee and shall bear the following legend: "The securities represented 
hereby are subject to the terms of an agreement between Tencor Instruments 
and the holder of such securities. Pursuant to the terms of such agreement, 
Tencor Instruments has the rights to purchase such securities under certain 
conditions. A copy of the agreement can be obtained from the Secretary of 
Tencor Instruments."

     5.  TERM. The Option expires and ceases to be exercisable upon the 
earlier of (i) ten years after the grant date specified in Item B above, or 
(ii) three months after the Optionee's employment or consultancy relationship 
with the Company is terminated.

     6.  TAXES. The Optionee acknowledges that (i) the Optionee has not been 
given by the Company and is not relying upon representations of the Company 
as to tax consequences of the grant or exercise of this Option, (ii) the 
foregoing tax consequences are known to be complex and dependent in part upon 
Optionee's particular circumstances, and (ii) the Optionee has consulted, 
and will consult at appropriate times, with Optionee's own tax adviser 
regarding such tax consequences.

     IN WITNESS WHEREOF, the parties have executed this Nonstatutory Stock 
Option Agreement as of the Effective Date.


                                       -----------------------------------------
TENCOR INSTRUMENTS                     Optionee

By
  --------------------------------     -----------------------------------------
Title                                  Optionee's Spouse*
     -----------------------------

* Optionee's spouse indicates by the execution of this Agreement his or her 
consent to be bound by the terms thereof as to his or her interests, whether 
as community property or otherwise, if any, in the option granted hereunder, 
and in any Option Shares purchased pursuant to this Agreement.

                                      -2-

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                           TENCOR INSTRUMENTS
                    INCENTIVE STOCK OPTION AGREEMENT

             (A)  Name of Optionee: ___________________
             (B)  Grant Date: _________________________
             (C)  Number of Shares: ___________________
             (D)  Exercise Price: _____________________
             (E)  Effective Date: _____________________
             (F)  Percentage to Vest at end Year One: ___%
             (G)  Percentage to Vest Monthly/Annually After Year One: ___%

     THIS INCENTIVE STOCK OPTION AGREEMENT (the "Agreement") is made and 
entered into as of the date set forth in Item E above (the "Effective Date") 
between Tencor Instruments, a California corporation (the "Company"), and the 
person named in Item A above ("Optionee").

     1.  GRANT.  The Company hereby grants to Optionee pursuant to the 
Company's 1993 Amended and Restated Equity Incentive Plan (the "Plan"), the 
terms and conditions of which are incorporated herein by this reference, an 
option (the "ISO") to purchase the number of shares (the "ISO Shares") of the 
Company's common stock listed in Item C above on the terms and conditions set 
forth herein and in the Plan.

     2.  VESTING OF ISO SHARES.  The vesting base date (the "Vesting Base 
Date") shall be the same date as the grant date set forth in Item B above; 
the ISO Shares shall vest on the first anniversary of the Vesting Base Date 
at the rate specified in Item F above; the ISO Shares shall vest at the end 
of each full period thereafter at the rate specified in Item G above.

     3.  EXERCISE OF THE ISO.  This ISO may be exercised in whole or part at 
any time. The exercise price shall be the price set forth in Item D above 
(the "Exercise Price"). Optionee hereby agrees that, in the event that the 
Company deems it necessary or advisable in the exercise of its discretion, 
the issuance of ISO Shares may be conditioned upon certain representations 
and acknowledgments by the person exercising the ISO.

         a.  EXERCISE BEFORE VESTING. The Optionee may exercise the ISO 
before vesting of the ISO Shares by delivering to the Company: (i) the 
Exercise Price, (ii) an executed copy of the Notice of Exercise attached 
hereto as Exhibit 1, and (iii) an executed copy of the Acknowledgment and 
Statement of Decision Regarding Election attached hereto as Exhibit 2. Share 
certificates representing ISO Shares purchased before vesting shall be held 
in escrow and released to the Optionee upon vesting, or at the Company's sole 
discretion, ISO Shares purchased before vesting may be issued in book-entry 
form without certification. The Company shall instruct the person maintaining 
the book-entry system that such ISO Shares shall not be transferred until 
such ISO Shares are vested or the Company's right of repurchase (as provided 
in Section 4 below) has otherwise terminated. As a condition to exercising 
the ISO before vesting of the ISO Shares, the Optionee shall execute such 
documents as are reasonably necessary to carry out the intent of this 
Section, including execution of an escrow agreement, the terms and conditions 
of which shall be determined by the Company at its sole discretion.

<PAGE>

         b.  EXERCISE AFTER VESTING. The Optionee may exercise the ISO after 
vesting of the ISO Shares by delivering to the Company: (i) the Exercise 
Price, and (ii) an executed copy of the Notice of Exercise attached hereto as 
Exhibit 1.

     4.  RIGHT OF REPURCHASE. The Company shall have a right to repurchase 
(the "Right of Repurchase"), at the price paid by the Optionee, any ISO 
Shares that have not vested. The Right of Repurchase shall terminate upon the 
later of: (i) 45 days after the date on which the Optionee ceases to be 
employed by, or a consultant to, the Company, or (ii) 30 days after the ISO 
is exercised. Upon exercise of the Right of Repurchase, the Optionee shall 
endorse and deliver to the Company the stock certificates, if any, 
representing the ISO Shares being repurchased and the Company shall pay the 
Optionee the repurchase price. Upon receipt of payment from the Company, the 
Optionee shall have no rights whatsoever in any ISO Shares repurchased by the 
Company. ISO Shares subject to the Right of Repurchase shall not be assigned, 
pledged, transferred, hypothecated or otherwise disposed of by the Optionee 
and shall bear the following legend: "The securities represented hereby are 
subject to the terms of an agreement between Tencor Instruments and the 
holder of such securities. Pursuant to the terms of such agreement, Tencor 
Instruments has the rights to purchase such securities under certain 
conditions. A copy of the agreement can be obtained from the Secretary of 
Tencor Instruments."

     5.  TERM. The ISO expires and ceases to be exercisable upon the earlier 
of (i) ten years after the grant date specified in Item B above, or (ii) 
three months after the Optionee's employment or consultancy relationship with 
the Company is terminated.

     6.  TAXES. The Optionee acknowledges that (i) the Optionee has not been 
given by the Company and is not relying upon representations of the Company 
as to tax consequences of the grant or exercise of this Option, (ii) the 
foregoing tax consequences are known to be complex and dependent in part upon 
Optionee's particular circumstances, and (iii) the Optionee has consulted, 
and will consult at appropriate times, with Optionee's own tax adviser 
regarding such tax consequences.

     IN WITNESS WHEREOF, the parties have executed this Incentive Stock 
Option Agreement as of the Effective Date.


                                       -----------------------------------------
TENCOR INSTRUMENTS                     Optionee

By
  --------------------------------     -----------------------------------------
Title                                  Optionee's Spouse*
     -----------------------------

* Optionee's spouse indicates by the execution of this Agreement his or her 
consent to be bound by the terms thereof as to his or her interests, whether 
as community property or otherwise, if any, in the option granted hereunder, 
and in any ISO Shares purchased pursuant to this Agreement.

                                      -2-