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                                                                   EXHIBIT 10.51


                        LICENSE REFERENCE NUMBER L004001

121900

         PATENT LICENSE AGREEMENT ("Agreement") dated December 15, 2000
("Effective Date") between INTERNATIONAL BUSINESS MACHINES CORPORATION, a New
York corporation ("IBM"), and IBIS TECHNOLOGY CORPORATION, a Massachusetts
corporation ("IBIS").

Under the License Agreement between the parties dated December 15, 2000
("Know-how Agreement"), IBM is licensing IBIS under certain know-how and other
rights related to IBM's proprietary process for implanting silicon wafers with
oxygen as practiced at its East Fishkill, NY, location, and IBIS is granting
certain rights to IBM. No patent licenses, express or implied, were granted by
either party under the Know-how Agreement. Each party desires to grant the other
certain rights under patents in connection with the know-how and other rights
granted under the Know-how Agreement. In consideration of the premises and
covenants herein contained, and of the parties' entry into the Know-how
Agreement, IBM and IBIS agree as follows:

SECTION 1.    DEFINITIONS

1.1 "Licensed Product" shall mean silicon wafers implanted with oxygen and
annealed in accordance with the Licensed Process.

1.2 "Licensed Process" shall have the meaning set forth in section 1.7 of the
Know-how Agreement.

1.3 "IBM Licensed Patents" shall mean all patents (U.S. or foreign), including
utility models but not including design patents, covering Licensed Products and
the Licensed Process, issued or issuing on patent applications that claim
inventions having an effective filing date on or before the Effective Date under
which patents or the applications therefor IBM or any of its Subsidiaries has
the right, at any time during the term of this Agreement, to grant licenses to
IBIS and its Subsidiaries of the scope granted herein without such grant or the
exercise of rights thereunder resulting in the payment of royalties or other
consideration by IBM to third parties (except for payments to Subsidiaries and
payments to third parties for inventions made by said third parties while
employed by IBM or any of its Subsidiaries), and any continuation,
continuation-in-part, divisional, reissue, reexamination and any equivalents
thereof. By way of example and not as a limitation, this definition of IBM
Licensed Patents includes U.S. Patent 5,930,643. Notwithstanding the foregoing
definition, "IBM Licensed Patents" shall not include patents directed at the
structure of implantation machines.

1.4 "IBIS Licensed Patents" shall mean all patents (U.S. or foreign) covering
Licensed Products and the Licensed Process and improvements thereto, including
utility models but not including design patents, issued or issuing on patent
applications that claim inventions having an effective filing date on or before
six (6) months after the term of this Agreement, under which patents or the
applications therefor IBIS or any of its Subsidiaries has the right, at any time
during the term of this Agreement, to grant licenses to IBM and its Subsidiaries
of the scope

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granted herein without such grant or the exercise of rights thereunder resulting
in the payment of royalties or other consideration by IBIS to third parties
(except for payments to Subsidiaries and payments to third parties for
inventions made by said third parties while employed by IBIS or any of its
Subsidiaries), and any continuation, continuation-in-part, divisional, reissue,
reexamination and any equivalents thereof. Notwithstanding the foregoing
definition, "IBIS Licensed Patents" shall not include patents directed at the
structure of implantation machines.

1.5 "Subsidiary" shall mean a corporation, company or other entity:

(a)      more than fifty percent (50%) of whose outstanding shares or securities
         (representing the right to vote for the election of directors or other
         managing authority) are, now or hereafter, owned or controlled,
         directly or indirectly, by a party hereto, or

(b)      which does not have outstanding shares or securities, as may be the
         case in a partnership, joint venture or unincorporated association, but
         more than fifty percent (50%) of whose ownership interest representing
         the right to make the decisions for such corporation, company or other
         entity is now or hereafter, owned or controlled, directly or
         indirectly, by a party hereto,

but such corporation, company or other entity shall be deemed to be a Subsidiary
only so long as such ownership or control exists.

SECTION 2.    GRANT OF RIGHTS

2.1 IBM grants to IBIS a worldwide, nonexclusive license under the IBM Licensed
Patents to make, import, export, and sell Licensed Products. No license to have
Licensed Products made by third parties is granted to IBIS hereunder. No license
is granted with respect to any item other than a Licensed Product,
notwithstanding that such other item may incorporate one or more Licensed
Products. The royalty for the license granted under this Section 2.1 is included
in the royalty payable by IBIS under the Know-how Agreement.

2.2 IBIS grants to IBM a worldwide, nonexclusive paid-up license under IBIS
Licensed Patents to make, have made, use, import, export, offer to sell, sell
and otherwise transfer wafers that are implanted with oxygen and annealed.

2.3 Subject to Section 2.4, the licenses granted herein shall include the right
of each party to grant sublicenses to its Subsidiaries existing on or after the
Effective Date, which sublicenses may include the right of sublicensed
Subsidiaries to sublicense other Subsidiaries of said party. No sublicense shall
be broader in any respect at any time during the life of this Agreement than the
license held at that time by the party that granted the sublicense.

2.4 A sublicense granted to a Subsidiary shall terminate on the earlier of:

(a)      the date such Subsidiary ceases to be a Subsidiary; and

(b)      the date of termination or expiration of the license of the party or
         Subsidiary that granted the sublicense. If a Subsidiary ceases to be a
         Subsidiary and holds any patents under which a party hereto is
         licensed, such license shall continue for the term defined herein.

2.5 Each party shall be responsible for the compliance by its sublicensed
Subsidiaries with the provisions of this Agreement.


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2.6 No license, immunity or other right is granted under this Agreement, either
directly or by implication, estoppel, or otherwise other than under the Licensed
Patents, or to parties acquiring any item from a party (or its licensed
Subsidiary) for the combination of such acquired item with any other item,
including other items provided by such party (or its licensed Subsidiary), or
for the use of any such combination even if such acquired item has no
substantial use other than as part of such combination.


SECTION 3.    TERM AND TERMINATION

3.1 Unless earlier terminated pursuant to Section 3.2, the term of this
Agreement shall be from the Effective Date until the expiration of the last to
expire patent licensed hereunder.

3.2 IBM shall have the right to terminate this agreement upon termination of the
Know-how Agreement due to the default of IBIS.

SECTION 4.    COMMUNICATION

4.1 Notices and other communications shall be sent by facsimile or by registered
or certified mail to the following address and shall be effective upon mailing:

         For IBM:                           For IBIS:
         Director of Licensing              Debra L. Nelson
         IBM Corporation                    IBIS Technology Corporation
         North Castle Drive, MD-NC119       32A Cherry Hill Drive
         Armonk, New York 10504-1785        Danvers, MA  01923
         Facsimile: (914) 765-4380          Facsimile: (978) 777-6570

4.2 A License Reference Number will be assigned to this Agreement upon
execution. This number should be included in all communications in connection
with this Agreement.

SECTION 5.    MISCELLANEOUS

5.1 (a) This Agreement may be assigned by a party only in connection with its
assignment of all rights, privileges, and obligations under the Know-how
Agreement (as permitted thereunder), and only to the assignee of such rights,
privileges, and obligations, provided that such assignee agrees to be bound by
all the terms and conditions of this Agreement, provided that in the case of an
assignment by IBM (other than pursuant to Section 5.1(b), the license granted
under Section 2.2 to "offer to sell" and "sell" shall be limited to wafers
implanted with oxygen, annealed and cleaned that have undergone further
processing, such limitation not to apply to the other rights granted under
Section 2.2. No other assignment of this Agreement, or assignment of rights or
delegation of obligations hereunder, is permitted. Any attempted assignment or
delegation in derogation of the foregoing shall be void. The licenses granted
hereunder by the assigning party shall survive its assignment of this Agreement
for the term hereof; the licenses granted hereunder to the assigning party and
its Subsidiaries shall terminate upon such assignment.

(b) Notwithstanding Section 5.1(a), a party which undergoes reorganization may
assign its rights and delegate its obligations under this Agreement to its legal
successor, provided that after


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the reorganization, the successor and its Subsidiaries will have essentially the
same assets as such party and its Subsidiaries had prior to the reorganization.

(c) A party assigning this Agreement shall provide written notice of the
assignment within 30 days after such assignment.

5.2 Neither party shall use or refer to this Agreement or any of its provisions
in any promotional activity.

5.3 Each party represents and warrants that it has the full right and power to
grant the license and release set forth in Section 2. Neither party makes any
other representation or warranty, express or implied, nor shall either party
have any liability in respect of any infringement of patents or other rights of
third parties due to the other party's operation under the license herein
granted.

5.4 Neither party shall have any obligation hereunder to institute any action or
suit against third parties for infringement of any of its Licensed Patents or to
defend any action or suit brought by a third party which challenges or concerns
the validity of any of its Licensed Patents. Neither party shall have any right
to institute any action or suit against third parties for infringement of any of
the other party's Licensed Patents. Neither party, nor any of its Subsidiaries,
is required to file any patent application, or to secure any patent or patent
rights, or to maintain any patent in force.

5.5 If any section of this Agreement is found by competent authority to be
invalid, illegal or unenforceable in any respect for any reason, the validity,
legality and enforceability of such Section in every other respect and the
remainder of this Agreement shall continue in effect so long as the Agreement
still expresses the intent of the parties. If the intent of the parties cannot
be preserved, this Agreement shall be either renegotiated or terminated.

5.6 This Agreement shall not be binding upon the parties until it has been
signed hereinbelow by or on behalf of each party, in which event it shall be
effective as of the Effective Date. No amendment or modification hereof shall be
valid or binding upon the parties unless made in writing and signed as
aforesaid.

5.7 This Agreement shall be construed, and the legal relations between the
parties hereto shall be determined, in accordance with the law of the State of
New York, United States of America, as such law applies to contracts signed and
fully performed in the State of New York.

5.8 The headings of sections are inserted for convenience of reference only and
are not intended to be a part of or to affect the meaning or interpretation of
this Agreement.


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         THIS AGREEMENT EMBODIES THE ENTIRE UNDERSTANDING OF THE PARTIES WITH
RESPECT TO THE LICENSED PATENTS, AND REPLACES ANY PRIOR ORAL OR WRITTEN
COMMUNICATION BETWEEN THEM.

AGREED TO:                                  AGREED TO:
IBIS TECHNOLOGY CORPORATION                 INTERNATIONAL BUSINESS
                                            MACHINES CORPORATION


By /s/ Martin J. Reid                       By /s/ Gerald Rosenthal
   --------------------------------            -------------------------
   Martin J. Reid                              Gerald Rosenthal
   CEO                                         Vice President

Date: Dec 20, 2000                          Date: 1-9-01
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