AMENDED AND RESTATED EXECUTIVE EMPLOYMENTAGREEMENT

Exhibit 10.1

AMENDED AND RESTATED EXECUTIVE EMPLOYMENT AGREEMENT

This Executive Employment Agreement is between CREDENCE SYSTEMS CORPORATION, a California corporation (the “Company”) and ASHOK BELANI, an individual (“Executive”). This Agreement shall become effective May 28, 2004 (the “Effective Time”).

1. POSITIONS AND RESPONSIBILITIES

a. Position and Term. Executive shall be employed by the Company for a period of twenty-six (26) months from the Effective Time, unless extended by mutual agreement of the parties as hereafter set forth (the “Term”). For the initial fourteen (14) months of the Term, Executive shall serve as Vice Chair of the Company’s Board of Directors (the “Vice Chair Period”). At the end of the Vice Chair Period, Executive shall remain employed by the Company in a position to be mutually agreed by the parties for the remaining twelve (12) months of the Term (“Post Vice-Chair Period”); provided, however, Credence will extend the term of Executive’s employment for a period to be mutually agreed by the parties in the event Executive shall not have realized the Minimum Amount with respect to the Options as contemplated by Section 3.03(b)(ii) of that certain Employment Agreement dated as of July 29, 2003 by and among NPTest Acquisition Corporation, NPTest Holding Corporation, and Executive, as of the last day of the Post Vice Chair Period . Executive shall perform such duties and responsibilities as are normally related to such position in accordance with the standards of the industry and any additional duties now or hereafter assigned to Executive by the Company. Executive shall abide by the rules, regulations, and practices as adopted or modified from time to time in the Company’s sole discretion.

b. Other Activities. Except upon the prior written consent of the Company, Executive will not, during the Vice Chair Period of this Agreement, (i) accept any other employment, or (ii) engage, directly or indirectly, in any other business activity (whether or not pursued for pecuniary advantage) that might interfere with Executive’s duties and responsibilities hereunder or create a conflict of interest with the Company.

c. No Conflict. Executive represents and warrants that Executive’s execution of this Agreement, Executive’s employment with the Company, and the performance of Executive’s proposed duties under this Agreement shall not violate any obligations Executive may have to any other employer, person or entity, including any obligations with respect to proprietary or confidential information of any other person or entity.

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2. COMPENSATION AND BENEFITS

a. Base Salary. The Company shall pay Executive a salary of Forty One Thousand Six Hundred Sixty-eight Dollars ($41,668) per month for the initial sixmonths of the Vice Chair Period. The Company shall pay Executive a salary of Thirty Three Thousand Three Hundred Thirty Four Dollars ($33,334) per month for the last eight months of the Vice Chair Period. During the Post Vice-Chair Period, the Company shall pay Executive a salary at the rate of Ten Thousand Dollars ($10,000) per month. In the event Executive’s term of employment is extended by mutual agreement of the parties after the Post Vice-Chair period, Executive shall be paid an amount mutually agreed by the parties. Executive’s salary shall be paid in accordance with the Company’s regularly established payroll practice.

b. Benefits. Executive shall be eligible to participate in the benefits made generally available by the Company to similarly-situated executives, in accordance with the benefit plans established by the Company, and as may be amended from time to time in the Company’s sole discretion.

c. Expenses. The Company shall reimburse Executive for reasonable business expenses incurred in the performance of Executive’s duties hereunder in accordance with the Company’s expense reimbursement guidelines.

d. Bonus. For fiscal year 2005, Executive shall be eligible for an annual target incentive bonus equal to Fifty Percent (50%) of his annual salary for such fiscal year (“Target Bonus”). During fiscal year 2005, Executive shall receive the percentage of his Target Bonus that equals the percentage of Target Bonus earned by the Company’s Chief Executive Officer for the year, which bonus shall be pro rated for that period of the fiscal year during which Executive served as Vice Chair of the Company’s Board of Directors. After the end of fiscal year 2005, Executive shall cease to be eligible for any bonus compensation.

3. AT-WILL EMPLOYMENT; TERMINATION

a. At-Will Termination. Either Executive or the Company may terminate Executive’s employment with the Company at any time, for any reason or no reason at all, upon thirty (30) days’ advance written notice.

b. Severance. Except in situations where the employment of Executive is terminated For Cause, By Death or By Disability (as defined in Section 4 below), in the event that the Company terminates Executive’s employment during the Term, Executive will be eligible to receive the remaining salary payments he would have received for any remaining portion of the Term,

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which shall be payable as salary continuation. In addition, except in situations where the employment of Executive is terminated For Cause or By Death, in the event that the Company terminates Executive’s employment during the Term or the employment of the Executive by the Company ceases by reason of the end of the Term, the Company shall pay the premiums for Executive’s COBRA coverage until the earlier of the following: (1) the later of that date (x) eighteen (18) months after the Effective Time or (y) six (6) months after the employment of the Executive by the Company ceases by reason of end of the Term or (2) that date the Executive becomes covered by another employer’s health plan. Where Executive’s employment has been terminated, Executive’s eligibility for the foregoing severance benefits is conditioned on Executive having first signed a release of claims in a form provided by the Company.

4. OTHER TERMINATIONS BY COMPANY

a. Termination for Cause. For purposes of this Agreement, “for Cause” shall mean: (i) Executive commits a crime involving dishonesty, breach of trust, or physical harm to any person; (ii) Executive willfully engages in conduct that is in bad faith and materially injurious to the Company, including but not limited to, misappropriation of trade secrets, fraud or embezzlement; (iii) Executive commits a material breach of this Agreement, which breach is not cured within twenty days after written notice to Executive from the Company; (iv) Executive willfully refuses to implement or follow a lawful policy or directive of the Company, which breach is not cured within twenty days after written notice to Executive from the Company; or (v) Executive willfully engages in misfeasance or malfeasance demonstrated by a pattern of failure to perform job duties diligently and professionally. The Company may terminate Executive’s employment for Cause at any time, without any advance notice. The Company shall pay to Executive all compensation to which Executive is entitled up through the date of termination for Cause, subject to any other rights or remedies of Employer under law; and thereafter all obligations of the Company under this Agreement shall cease.

b. By Death. Executive’s employment shall terminate automatically upon Executive’s death. The Company shall pay to Executive’s beneficiaries or estate, as appropriate, any compensation then due and owing. Thereafter all obligations of the Company under this Agreement shall cease. Nothing in this Section shall affect any entitlement of Executive’s heirs or devisees to the benefits of any life insurance plan or other applicable benefits.

c. By Disability. If Executive becomes eligible for the Company’s long term disability benefits or if, in the sole opinion of the Company, Executive is unable to carry out the responsibilities and functions of the position held by

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Executive by reason of any physical or mental impairment for more than ninety (90) consecutive days or more than one hundred and twenty (120) days in any twelve-month period, then, to the extent permitted by law, the Company may terminate Executive’s employment. The Company shall pay to Executive all compensation to which Executive is entitled up through the date of termination, and thereafter all obligations of the Company under this Agreement shall cease. Nothing in this Section shall affect Executive’s rights under any disability plan in which Executive is a participant.

5. TERMINATION OBLIGATIONS

a. Return of Property. Executive agrees that all property (including without limitation all equipment, tangible proprietary information, documents, records, notes, contracts and computer-generated materials) furnished to or created or prepared by Executive incident to Executive’s employment belongs to the Company and shall be promptly returned to the Company upon termination of Executive’s employment.

b. Resignation and Cooperation. Upon termination of Executive’s employment, Executive shall be deemed to have resigned from all offices and directorships then held with the Company. Following any termination of employment, Executive shall cooperate with the Company in the winding up of pending work on behalf of the Company and the orderly transfer of work to other employees. Executive shall also cooperate with the Company in the defense of any action brought by any third party against the Company that relates to Executive’s employment by the Company.

6. INVENTIONS AND PROPRIETARY INFORMATION; PROHIBITION ON THIRD PARTY INFORMATION

a. Proprietary Information Agreement. Executive agrees to sign and be bound by the terms of the Company’s standard Employee Proprietary Information and Inventions Agreement (“Proprietary Information Agreement”).

b. Non-Solicitation. Executive acknowledges that because of Executive’s position in the Company, Executive will have access to material intellectual property and confidential information. During the term of Executive’s employment and for a period of twelve (12) months thereafter, in addition to Executive’s other obligations hereunder or under the Proprietary Information Agreement, Executive shall not, for Executive or any third party, directly or indirectly (a) divert or attempt to divert from the Company any business of any kind, including without limitation the solicitation of or interference with any of its customers, clients, members, business partners or suppliers, or (b) solicit or otherwise induce any person employed by the Company to terminate his employment.

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c. Non-Disclosure of Third Party Information. Executive represents and warrants and covenants that Executive shall not disclose to the Company, or use, or induce the Company to use, any proprietary information or trade secrets of others at any time, including but not limited to any proprietary information or trade secrets of any former employer, if any; and Executive acknowledges and agrees that any violation of this provision shall be grounds for Executive’s immediate termination and could subject Executive to substantial civil liabilities and criminal penalties. Executive further specifically and expressly acknowledges that no officer or other employee or representative of the Company has requested or instructed Executive to disclose or use any such third party proprietary information or trade secrets.

d. Non-Competition. Employee understands and agrees that Company is engaged in the business of designing, manufacturing, selling and servicing engineering validation test and automatic production test equipment and software design products used for assisting in the design of and testing of semiconductor integrated circuits (the “Business”). As an inducement to Company to enter into the merger transaction with NPTest Holdings Corporation and in consideration of the payments contemplated hereby, Employee agrees that for a period of one (1) year from and after the termination of his Employment with the Company, Employee shall not, anywhere in North America or Europe, directly or indirectly, (1) engage, without the express prior written consent of Company, in any business or activity, whether as an employee, consultant, partner, advisor, independent contractor, general partner, officer, director, member, stockholder or other equity holder, investor, lender or guarantor of any corporation, partnership or other entity, principal, agent, representative, or in any other individual, corporate or representative capacity (without limitation by specific enumeration of the foregoing) involving the Business, or (2) render any services or provide any advice to any business, activity or person involving the Business, or (3) allow his name to be used in connection with any business, activity or person that engages in the Business. Notwithstanding the foregoing, Employee may own, directly or indirectly, solely as an investment up to one percent (1%) of any class of “publicly traded securities” of any person that owns or operates a business that is competitive or substantially similar to the Business. For the purposes of this section, the term “publicly traded securities” shall mean securities that are traded on a national securities exchange or listed on the NASDAQ National Market. In addition, Employee will provide written notice to Company’s General Counsel of any proposed employment or consulting positions during this period.

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7. ARBITRATION

Executive and the Company agree that any dispute, controversy or claim between them shall be settled exclusively by final and binding arbitration in accordance with the National Rules for the Resolution of Employment Disputes of the American Arbitration Association (the “AAA Rules”). A neutral and impartial arbitrator shall be chosen by mutual agreement of the parties or, if the parties are unable to agree upon an arbitrator within a reasonable period of time, then a neutral and impartial arbitrator shall be appointed in accordance with the arbitrator nomination and selection procedure set forth in the AAA Rules. The arbitrator shall apply the same substantive law, with the same statutes of limitations and remedies, which would apply if the claims were brought in court. The arbitrator also shall prepare a written decision containing the essential findings and conclusions upon which the decision is based. Either party may bring an action in court to compel arbitration under this Agreement or to enforce an arbitration award. Otherwise, neither party shall initiate or prosecute any lawsuit in any way related to any claim subject to this agreement to arbitrate. Any arbitration held pursuant to this Paragraph shall take place in Santa Clara County, California. Each party shall pay its own costs and attorneys’ fees, unless a party prevails on a statutory claim and the statute provides that the prevailing party is entitled to payment of its attorneys’ fees. In that case, the arbitrator may award reasonable attorneys’ fees and costs to the prevailing party as provided by law. The Company agrees to pay the costs and fees of the arbitrator. THE PARTIES UNDERSTAND AND AGREE THAT THIS AGREEMENT CONSTITUTES A WAIVER OF THEIR RIGHT TO A TRIAL BY JURY OF ANY CLAIMS OR CONTROVERSIES COVERED BY THIS AGREEMENT.

8. AMENDMENTS; WAIVERS; REMEDIES

This Agreement may not be amended or waived except by a writing signed by Executive and by a duly authorized representative of the Company other than Executive. Failure to exercise any right under this Agreement shall not constitute a waiver of such right. Any waiver of any breach of this Agreement shall not operate as a waiver of any subsequent breaches. All rights or remedies specified for a party herein shall be cumulative and in addition to all other rights and remedies of the party hereunder or under applicable law.

9. ASSIGNMENT; BINDING EFFECT

a. Assignment. The performance of Executive is personal hereunder, and Executive agrees that Executive shall have no right to assign and shall not

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assign or purport to assign any rights or obligations under this Agreement. This Agreement may be assigned or transferred by the Company; and nothing in this Agreement shall prevent the consolidation, merger or sale of the Company or a sale of any or all or substantially all of its assets.

b. Binding Effect. Subject to the foregoing restriction on assignment by Executive, this Agreement shall inure to the benefit of and be binding upon each of the parties; the affiliates, officers, directors, agents, successors and assigns of the Company; and the heirs, devisees, spouses, legal representatives and successors of Executive.

10. NOTICES

All notices or other communications required or permitted hereunder shall be made in writing and shall be deemed to have been duly given if delivered: (a) by hand; (b) by a nationally recognized overnight courier service; or (c) by United States first class registered or certified mail, return receipt requested, to the principal address of the other party, as set forth below. The date of notice shall be deemed to be the earlier of (i) actual receipt of notice by any permitted means, or (ii) five business days following dispatch by overnight delivery service or the United States Mail. Executive shall be obligated to notify the Company in writing of any change in Executive’s address. Notice of change of address shall be effective only when done in accordance with this paragraph.

Company’s Notice Address:

Credence Systems Corporation

1421 California Circle

Milpitas, CA 95035

Executive’s Notice Address:

12101 Dawn Lane

Los Altos Hills, CA 94022

11. SEVERABILITY

If any provision of this Agreement shall be held by a court or arbitrator to be invalid, unenforceable, or void, such provision shall be enforced to the fullest extent permitted by law, and the remainder of this Agreement shall remain in full force and effect. In the event that the time period or scope of any provision is declared by a court or arbitrator of competent jurisdiction to exceed the maximum

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time period or scope that such court or arbitrator deems enforceable, then such court or arbitrator shall reduce the time period or scope to the maximum time period or scope permitted by law.

12. TAXES

All amounts paid under this Agreement (including without limitation Base Salary and Severance) shall be paid less all applicable state and federal tax withholdings and any other withholdings required by any applicable jurisdiction.

13. GOVERNING LAW

This Agreement shall be governed by and construed in accordance with the laws of the State of California.

14. INTERPRETATION

This Agreement shall be construed as a whole, according to its fair meaning, and not in favor of or against any party. Sections and section headings contained in this Agreement are for reference purposes only, and shall not affect in any manner the meaning or interpretation of this Agreement. Whenever the context requires, references to the singular shall include the plural and the plural the singular.

15. OBLIGATIONS SURVIVE TERMINATION OF EMPLOYMENT

Executive agrees that any and all of Executive’s obligations under this agreement shall survive the termination of employment and the termination of this Agreement.

16. COUNTERPARTS

This Agreement may be executed in any number of counterparts, each of which shall be deemed an original of this Agreement, but all of which together shall constitute one and the same instrument.

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17. AUTHORITY

Each party represents and warrants that such party has the right, power and authority to enter into and execute this Agreement and to perform and discharge all of the obligations hereunder; and that this Agreement constitutes the valid and legally binding agreement and obligation of such party and is enforceable in accordance with its terms.

18. ENTIRE AGREEMENT

This Agreement is intended to be the final, complete, and exclusive statement of the terms of Executive’s employment by the Company and may not be contradicted by evidence of any prior or contemporaneous statements or agreements, except for agreements specifically referenced herein (including the Executive Proprietary Information and Inventions Agreement, the Arbitration Agreement, and the Stock Plan and Stock Option Agreement of the Company). To the extent that the practices, policies or procedures of the Company, now or in the future, apply to Executive and are inconsistent with the terms of this Agreement, the provisions of this Agreement shall control. Any subsequent change in Executive’s duties, position, or compensation will not affect the validity or scope of this Agreement.

19. EXECUTIVE ACKNOWLEDGEMENT

EXECUTIVE ACKNOWLEDGES THAT HE HAS HAD THE OPPORTUNITY TO CONSULT LEGAL COUNSEL CONCERNING THIS AGREEMENT, THAT EXECUTIVE HAS READ AND UNDERSTANDS THE AGREEMENT, THAT EXECUTIVE IS FULLY AWARE OF ITS LEGAL EFFECT, AND THAT EXECUTIVE HAS ENTERED INTO IT FREELY BASED ON HIS OWN JUDGMENT AND NOT ON ANY REPRESENTATIONS OR PROMISES OTHER THAN THOSE CONTAINED IN THIS AGREEMENT.

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IN WITNESS WHEREOF, the parties have duly executed this Agreement on December 6, 2004.

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