Exhibit 10.1

ADE CORPORATION  2000 EMPLOYEE STOCK OPTION PLAN1

1. PURPOSES OF THE PLAN

The ADE Corporation 2000 Employee Stock Option Plan is intended to encourage ownership of shares of the Common Stock of ADE Corporation (the "Company") by key
employeesand consultantsof the Company or of its Affiliates in order to attract such persons, to induce them to work for the benefit of the Company or
of an Affiliate, and to provide additional incentive for them to promote the long-term success of the Company or of an Affiliate. The Company desires to reward its key employees and consultantsequitably for their service, value, and commitment to the Company. The Company believes that the Plan will cause participants to
contribute materially to the growth of the Company, thereby benefiting the Company's shareholders.

2. DEFINITIONS

Unless otherwise specified or unless the context otherwise requires, the following terms, as used in the Plan, have the following meanings:



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3. SHARES SUBJECT TO THE PLAN

The number of Shares subject to the Plan as to which Stock Rights may be granted from time to time shall be 900,000, plus the number of shares of Common Stock
previously reserved for the granting of options under either the Company's 1995 Stock Option Plan or 1997 Stock Option Plan which are not granted under either of those plans or which are not exercised
and cease to be outstanding by reason of cancellation or otherwise, or the equivalent of such number of Shares after the Committee, in its sole discretion, has interpreted the effect of any stock
split, stock dividend, combination, recapitalization, or similar transaction in accordance with Section 16 of the Plan.

If
an Option granted hereunder ceases to be "outstanding", in whole or in part, the Shares which were subject to such Option shall also be available for the granting of other Stock
Rights under the Plan. Any Stock Right shall be treated as "outstanding" until such Stock Right is exercised in full or terminates or expires under the provisions of the Plan, or by agreement of the
parties to the pertinent Stock Agreement, without having been exercised in full.

4. ADMINISTRATION OF THE PLAN

The Plan shall be administered by the Committee. The Committee shall be comprised of two or more members of the Board of Directors, all of whom shall be
Non-employee Directors as defined in Rule 16b-3 under the Exchange Act and "outside directors" as that term is used in Section 162 of the Code and the regulations
promulgated thereunder, or the entire Board of Directors acting as such a committee. Any provision in this Plan with respect to the Committee contrary to Rule 16b-3 or Code
Section 162 shall be deemed null and void to the extent permitted by law and deemed appropriate by the Committee. The Committee may delegate authority to the Chief Executive Officer to grant
Stock Rights with respect to a fixed number of Shares, to be reserved from time to time for such purpose by vote of the Committee, toKey Employees;
provided, however, that no such delegation shall be

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permitted with respect to the grant of Stock Rights to any person who is an officer or director of the Company for purposes of Section 16(b) of the Exchange Act.

Subject
to the provisions of the Plan, the Committee is authorized to:



provided,
however, that all such interpretations, rules, determinations, terms, and conditions shall be made and prescribed in the context of preserving the tax status under Code Section 422 of
those Options which are designated as ISOs and shall be in compliance with any applicable provisions of Rule 16b-3 under the Exchange Act. Subject to the foregoing, the
interpretation and construction by the Committee of any provisions of the Plan or of any Stock Right granted under it shall be final, unless otherwise determined by the Board of Directors, if the
Committee is other than the Board of Directors.

The
Committee may employ attorneys, consultants, accountants, or other persons, and the Committee, the Company, and its officers and directors shall be entitled to rely upon the advice,
opinions, or valuations of such persons. All actions taken and all interpretations and determinations made by the Committee in good faith shall be final and binding upon the Company, all Participants,
and all other interested persons. No member or agent of the Committee shall be personally liable for any action, determination, or interpretation made in good faith with respect to the Plan or grants
hereunder. Each member of the Committee shall be indemnified and held harmless by the Company against any cost or expense (including counsel fees) reasonably incurred by him or liability (including
any sum paid in settlement of a claim with the approval of the Company) arising out of any act or omission to act in connection with the Plan unless arising out of such member's own fraud or bad
faith. Such indemnification shall be in addition to any rights of indemnification the members of the Committee
may have as directors or otherwise under the by-laws of the Company, or any agreement, vote of stockholders, or disinterested directors, or otherwise.

5. ELIGIBILITY FOR PARTICIPATION

The Committee shall, in its sole discretion, name the Participants in the Plan, provided, however, that each Participant must be a Key Employee of the Company or
of an Affiliate at the time a Stock Right is granted. Notwithstanding the foregoing, the Committee may authorize the grant of a Stock Right to a person not then an employee of the Company or of an
Affiliate; provided, however, that the actual grant of such Stock Right shall be conditioned upon such person becoming eligible to become a Participant at or prior to the time of execution of the
Stock Agreement evidencing such Stock Right.

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The granting of any Stock Right to any individual shall neither entitle that individual to, nor disqualify him or her from, participation in other grants of Stock Rights.

6. TERMS AND CONDITIONS OF OPTIONS

(a)GENERAL.Each Option shall be set forth in writing in a Stock Agreement, duly executed by the Company and,
to the extent required by law or requested by the Company, by the Participant. The Committee may provide that Options be granted subject to such conditions as the Committee may deem appropriate,
including, without limitation, subsequent approval by the shareholders of the Company of this Plan or any amendments thereto; provided, however, that the option price per share of the Shares covered
by each Option shall not be less than the par value per share of the Common Stock. Each Stock Agreement shall state the number of Shares to which it pertains, the date or dates on which it first is
exercisable, and the date after which it may no longer be exercised. Option rights may accrue or become exercisable in installments over a period of time, or upon the achievement of certain conditions
or the attainment of stated goals or events. Exercise of any Option may be conditioned upon the Participant's execution of a Share purchase agreement in form satisfactory to the Committee providing
for certain protections for the Company and its other shareholders, including requirements that the Participant's or the Participant's Survivors' right to sell or transfer the Shares may be
restricted, and the Participant or the Participant's Survivors may be required to execute letters of investment intent and to acknowledge that the Shares will bear legends noting any applicable
restrictions.

(b)ISOS.In addition to the minimum standards set forth in paragraph (a) of this Section 6, ISOs
shall be subject to the following terms and conditions, with such additional restrictions or changes as the
Committee determines are appropriate but not in conflict with Code Section 422 and relevant regulations and rulings of the Internal Revenue Service:



(c)LIMITATION ON NUMBER OF OPTIONS GRANTED.Notwithstanding anything in the Plan to the contrary, no
Participant shall be granted Options in any calendar year for the purchase of more than 75,000 Shares.

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7. TERMS AND CONDITIONS OF STOCK AWARDS

Each Stock Award shall be set forth in a Stock Agreement, duly executed by the Company and, to the extent required by law or requested by the Company, by the
Participant. The Stock Agreement shall be in the form approved by the Committee, with such changes and modifications to such form as the Committee, in its discretion, shall approve with respect to any
particular Participant or Participants. The Stock Agreement shall contain terms and conditions which the Committee determines to be
appropriate and in the best interest of the Company; provided, however, that the purchase price per share of the Shares covered by each Stock Award shall not be less than the par value per Share. Each
Stock Agreement shall state the number of Shares to which the Stock Award pertains, the date prior to which the Stock Award must be exercised by the Participant, and the terms of any right of the
Company to reacquire the Shares subject to the Stock Award, including the time and events upon which such rights shall accrue and the purchase price therefor, and any restrictions on the
transferability of such Shares.

8. EXERCISE OF STOCK RIGHTS AND ISSUANCE OF SHARES

A Stock Right (or any part or installment thereof) shall be exercised by giving written notice to the Company, together with provision for payment of the full
purchase price in accordance with this Section for the Shares as to which such Stock Right is being exercised, and upon compliance with any other conditions set forth in the Stock Agreement. Such
written notice shall be signed by the person exercising the Stock Right, shall state the number of Shares with respect to which the Stock Right is being exercised, and shall contain any representation
required by the Plan or the Stock Agreement.

Payment
of the purchase price for the Shares as to which such Stock Right is being exercised shall be made (i) in United States dollars in cash or by check, (ii) through
delivery of shares of Common Stock already owned by the Participant not subject to any restriction under any plan and having a Fair Market Value equal as of the date of exercise to the cash exercise
price of the Stock Right, (iii) at the discretion of the Committee, by any other means, including a promissory note of the Participant, which the Committee determines to be consistent with the
purpose of this Plan and applicable law, (iv) at the discretion of the Committee, in accordance with a cashless exercise program established with a securities brokerage firm and approved by the
Committee, or (v) at the discretion of the Committee, by any combination of (i), (ii), (iii), and (iv) above. Notwithstanding the foregoing, the Committee shall accept only such payment
on exercise of an ISO as is permitted by Section 422 of the Code.

The
Company shall reasonably promptly deliver the Shares as to which such Stock Right was exercised to the Participant (or to the Participant's Survivors, as the case may be). In
determining what constitutes "reasonably promptly," it is expressly understood that the delivery of the Shares may be delayed by the Company in order to comply with any law or regulation which
requires the Company to take any action with respect to the Shares prior to their issuance. The Shares shall, upon delivery, be fully paid, non-assessable Shares.

9. RIGHTS AS A SHAREHOLDER

No Participant to whom a Stock Right has been granted shall have rights as a shareholder with respect to any Shares covered by such Stock Right, except after due
exercise thereof and tender of the full purchase price for the Shares being purchased pursuant to such exercise and registration of the Shares in the Company's share register in the name of the
Participant.

10. ASSIGNABILITY AND TRANSFERABILITY OF STOCK RIGHTS

ISOs and, except as otherwise provided in the pertinent Stock Agreement, NQSOs and Stock Awards shall not be transferable by the Participant other than by will or
by the laws of descent and distribution or pursuant to a qualified domestic relations order as defined by the Code or Title I of the

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Employee Retirement Income Security Act of 1974 or the rules thereunder; provided, however, that the designation of a beneficiary of a Stock Right by a Participant shall not be deemed a transfer
prohibited by this Section. Except as provided in the preceding sentence or as otherwise permitted under an NQSO or Stock Award Stock Agreement, a Stock Right shall be exercisable, during the
Participant's lifetime, only by such Participant (or by his or her legal representative) and shall not be assigned, pledged, or hypothecated in any way (whether by operation of law or otherwise) and
shall not be subject to execution, attachment, or similar process. Any attempted transfer, assignment, pledge, hypothecation, or other disposition of any Stock Right or of any rights granted
thereunder contrary to the provisions of this Plan, or the levy of any attachment or similar process upon a Stock Right, shall be null and void.

11. EFFECT OF TERMINATION OF SERVICE



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12. EFFECT OF TERMINATION OF SERVICE FOR "CAUSE"

Except as otherwise provided in the pertinent Stock Agreement, in the event of a Termination of Service of a Participant "for cause," all outstanding and
unexercised Stock Rights as of the date the Participant is notified his or her service is terminated "for cause" will immediately be forfeited. For purposes of this Section 12, "cause" shall
include (and is not limited to) dishonesty with respect to the Company and its Affiliates, insubordination, substantial malfeasance or nonfeasance of duty, unauthorized disclosure of confidential
information, conduct substantially prejudicial to the business of the Company or any Affiliate, and termination by the Participant in violation of an agreement by the Participant to remain in the
employor serviceof the Company or an Affiliate. The determination of the Committee as to the existence of cause will be conclusive on the Participant
and the Company. "Cause" is not limited to events which have occurred prior to a Participant's Termination of Service, nor is it necessary that the Committee's finding of "cause" occur prior to
termination. If the Committee determines, subsequent to a Participant's Termination of Service but prior to the exercise of a Stock Right, that either prior or subsequent to the Participant's
termination the Participant engaged in conduct which would constitute "cause," then the right to exercise any Stock Right shall be forfeited. Any definition in an agreement between a Participant and
the Company or an Affiliate which contains a conflicting definition of "cause" for termination and which is in effect at the time of such termination shall supersede the definition in this Plan with
respect to that Participant.

13. EFFECT OF TERMINATION OF SERVICE FOR DISABILITY

Except as otherwise provided in the pertinent Stock Agreement, in the event of a Termination of Service by reason of Disability, the Disabled Participant may
exercise any Stock Right granted to him or her to the extent exercisable but not exercised on the date of Disability. A Disabled Participant may exercise such rights only within a period of not more
than one (1) year after the date that the Participant became Disabled or, if earlier, within the originally prescribed term of the Stock Right.

The
Committee shall make the determination both of whether Disability has occurred and the date of its occurrence (unless a procedure for such determination is set forth in another
agreement between the Company and such Participant, in which case such procedure shall be used for such determination). If requested, the Participant shall be examined by a physician selected or
approved by the Committee, the cost of which examination shall be paid for by the Company.

14. EFFECT OF DEATH WHILE AN EMPLOYEE

Except as otherwise provided in the pertinent Stock Agreement, in the event of death of a Participant while the Participant is an employee of or consultant
tothe Company or an Affiliate, any Stock Rights granted to such Participant may be exercised by the Participant's Survivors to the extent
exercisable but not exercised on the date of death. Any such Stock Right must be exercised within one (1) year after the date of death of the Participant.

15. PURCHASE FOR INVESTMENT

Unless the offering and sale of the Shares to be issued upon the particular exercise of a Stock Right shall have been effectively registered under the Securities
Act of 1933, as now in force or hereafter amended (the "Securities Act"), the Company shall be under no obligation to issue the Shares covered by such exercise unless and until the following
conditions have been fulfilled:



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The
Company may delay issuance of the Shares until completion of any action or obtaining of any consent which the Company deems necessary under any applicable law (including, without
limitation, state securities or "blue sky" laws).

16. ADJUSTMENTS

Upon the occurrence of any of the following events, a Participant's rights with respect to any Stock Right granted to him or her hereunder which have not
previously been exercised in full shall be adjusted as hereinafter provided, unless otherwise specifically provided in the written agreement between the Participant and the Company relating to such
Stock Right or in any employment agreement between a Participant and the Company or an Affiliate:

(a)STOCK DIVIDENDS AND STOCK SPLITS.If the shares of Common Stock shall be subdivided or combined into a
greater or smaller number of shares or if the Company shall issue any shares of Common Stock as a stock dividend on its outstanding Common Stock, the number of shares of Common Stock deliverable upon
the exercise of such Stock Right shall be appropriately increased or decreased proportionately, and appropriate adjustments shall be made in the purchase price per share to reflect such subdivision,
combination, or stock dividend

(b)MERGERS OR CONSOLIDATIONS.If the Company is to be consolidated with or acquired by another entity in a
merger, or in the event of a sale of all or substantially all of the Company's assets (an "Acquisition"), the Company may take such action with respect to outstanding Stock Rights as the Committee or
the Board of Directors may deem to be equitable and in the best interests of the Company and its stockholders under the circumstances, including, without limitation, (i) giving the Participant
reasonable advance notice of the pendency of the Acquisition and accelerating the vesting of the Stock Rights so that they become exercisable in full immediately prior to the Acquisition,
(ii) making appropriate provision for the continuation of the Stock Rights by substituting on an equitable basis for the shares then subject to the Options either the consideration payable with
respect to the outstanding shares of Common Stock in connection with the Acquisition or securities of any successor or acquiring entity, or (iii) giving the Participant reasonable advance
notice of the pendency of
the Acquisition and canceling the Stock Rights effective upon the Acquisition if they are not exercised prior to the Acquisition.

(c)RECAPITALIZATION OR REORGANIZATION.In the event of a recapitalization or reorganization of the Company
(other than a transaction described in paragraph (b) of this Section 16) pursuant to which securities of the Company or of another corporation are issued with respect to the outstanding
shares of Common Stock, a Participant upon exercising a Stock Right shall be entitled to receive for the purchase price paid upon such exercise the securities he or she would have received if he or
she had exercised such Stock Right prior to such recapitalization or reorganization.

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(d)MODIFICATION OF ISOS.Notwithstanding the foregoing, any adjustments made pursuant to paragraph (a),
(b), or (c) of this Section 16 with respect to ISOs shall be made only after the Committee determines whether such adjustments would constitute a "modification" of such ISOs (as that
term is defined in Section 424(h) of the Code) or would cause any adverse tax consequences for the holders of such ISOS. If the Committee determines that such adjustments made with respect to
ISOs would constitute a modification of such ISOs, it may refrain from making such adjustments, unless the holder of an ISO specifically requests in writing that such adjustment be made and such
writing indicates that the holder has full knowledge of the consequences of such "modification" on his or her income tax treatment with respect to the ISO.

17. FRACTIONAL SHARES

No fractional share shall be issued under the Plan, and the person exercising any Stock Right shall receive from the Company cash in lieu of any such fractional
share equal to the Fair Market Value thereof determined in good faith by the Board of Directors of the Company.

18. CONVERSION OF ISOS INTO NON-QUALIFIED OPTIONS; TERMINATION OF ISOS.

Any Options granted under this Plan which do not meet the requirements of the Code for ISOs shall automatically be deemed to be NQSOs without further action on
the part of the Committee. The Committee, at the written request of any Participant, may in its discretion take such actions as may be necessary to convert such Participant's ISOs (or any portion
thereof) that have not been exercised on the date of conversion into NQSOs at any time prior to the expiration of such ISOs, regardless of whether the Participant is an employee of the Company or an
Affiliate at the time of such conversion. Such actions may include, but not be limited to, extending the exercise period or reducing the exercise price of the appropriate installments of such Options.
At the time of such conversion, the Committee (with the consent of the Participant) may impose such conditions on the exercise of the resulting NQSOs as the Committee in its discretion may determine,
provided that such conditions shall not be
inconsistent with this Plan. Nothing in the Plan shall be deemed to give any Participant the right to have such Participant's ISOs converted into NQSOs, and no such conversion shall occur until and
unless the Committee takes appropriate action. The Committee, with the consent of the Participant, may also terminate any portion of any ISO that has not been exercised at the time of such
termination.

19. WITHHOLDING

In the event that any federal, state, or local income taxes, employment taxes, Federal Insurance Contributions Act ("FICA") withholdings, or other amounts are
required by applicable law or governmental regulation to be withheld from the Participant's salary, wages, or other remuneration in connection with the exercise of a Stock Right or a Disqualifying
Disposition (as defined in Section 20), the Participant shall advance in cash to the Company, or to any Affiliate of the Company which employs or employed the Participant, the amount of such
withholdings unless a different withholding arrangement, including the use of shares of the Company's Common Stock, is authorized by the Committee (and permitted by law); provided, however, that with
respect to persons subject to Section 16 of the Exchange Act, any such withholding arrangement shall be in compliance with any applicable provisions of Rule 16b-3 promulgated
under Section 16 of the Exchange Act. For purposes hereof, the Fair Market Value of any shares withheld for purposes of payroll withholding shall be determined in the manner provided in
Section 2 hereof, as of the most recent practicable date prior to the date of exercise. If the Fair Market Value of the shares withheld is less than the amount of payroll withholdings required,
the Participant may be required to advance the difference in cash to the Company or the Affiliate employer. The Committee in its discretion may condition the exercise of an Option for less than the
then Fair Market Value on the Participant's payment of such additional withholding.

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20. NOTICE TO COMPANY OF DISQUALIFYING DISPOSITION

Each Key Employee who receives an ISO must agree to notify the Company in writing immediately after the Key Employee makes a Disqualifying Disposition of any
Shares acquired pursuant to the exercise of an ISO. A Disqualifying Disposition is any disposition (including any sale) of such shares before the later of (a) two years after the date the Key
Employee was granted the ISO, or (b) one year after the date the Key Employee acquired Shares by exercising the ISO. If the Key Employee has died before such Shares are sold, these holding
period requirements do not apply and no Disqualifying Disposition can occur thereafter.

21. EFFECTIVE DATE; TERMINATION OF THE PLAN

The Plan shall be effective on June 21, 2000, the date it was approved by the Board of Directors. Stock Rights may be granted under the Plan on and after
its effective date; provided, however, that any such Stock Rights shall be null and void if the Plan is not approved by the stockholders of the Company within twelve (12) months after the
effective date. The Plan will terminate on June 21, 2010, the date which is ten (10) years from the date of its approval by the Board of Directors. The Plan may be terminated at an
earlier date by vote of the stockholders of the Company; provided, however, that any such earlier termination will not affect any Stock Rights granted or Stock Agreements executed prior to the
effective date of such termination.

22. AMENDMENT OF THE PLAN

The Plan may be amended by the stockholders of the Company. The Plan may also be amended by the Board of Directors or the Committee, including, without
limitation, to the extent necessary to qualify any or all outstanding Stock Rights granted under the Plan or Stock Rights to be granted under the Plan for favorable federal income tax treatment
(including deferral of taxation upon exercise) as may be afforded incentive stock options under Section 422 of the Code, to the extent necessary to ensure the qualification of the Plan under
Rule 16b-3 under the Exchange Act, and to the extent necessary to qualify the shares issuable upon exercise of any outstanding Stock Rights granted, or Stock Rights to be granted,
under the Plan for listing on any national securities exchange or quotation in any national automated quotation system of securities dealers. Any amendment approved by the Board of Directors or the
Committee which is of a scope that requires stockholder approval in order to ensure favorable federal income tax treatment for any ISOs or requires stockholder approval in order to ensure the
compliance of the Plan with Rule 16b-3 or Section 162(m) of the Code shall be subject to obtaining such stockholder approval. No modification or amendment of the Plan shall
adversely affect any rights under a Stock Right previously granted to a Participant without such Participant's consent.

In
its discretion, the Committee may amend any term or condition of any outstanding Stock Right, provided (i) such term or condition as amended is permitted by the Plan,
(ii) if the amendment is adverse to the Participant, such amendment shall be made only with the consent of the Participant, (iii) any such amendment of any ISO shall be made only after
the Committee determines whether such amendment would constitute a "modification" of any Stock Right which is an ISO (as that term is defined in Section 424(h) of the Code) or would cause any
adverse tax consequences for the holder of such ISO, and (iv) with respect to any Stock Right held by any Participant who is subject to the provisions of Section 16(a) of the 1934 Act,
any such amendment shall be made only after the Committee determines whether such amendment would constitute the grant of a new Stock Right.

23. EMPLOYMENT OR OTHER RELATIONSHIP

Nothing in the Plan or any Stock Agreement shall be deemed to prevent the Company or an Affiliate from terminating the employment status of a Participant, nor to
prevent a Participant from

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terminating his or her own employment, or to give any Participant a right to be retained in employment or other service by the Company or any Affiliate for any period of time.

24. GOVERNING LAW

This Plan shall be construed and enforced in accordance with the law of the Commonwealth of Massachusetts.

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