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                                                                     EXHIBIT 3.0

                AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

     BTU International, Inc., a corporation organized and existing under the
General Corporation law of the State of Delaware (the "corporation"), does
hereby certify as follows:

     (a) The name under which the corporation was originally incorporated was B
& B International Holdings, Inc. The date of filing of the original Certificate
of Incorporation with the Delaware Secretary of State was June 3, 1982.

     (b) The text of the Restated Certificate of Incorporation as amended and
restated hereby and as duly adopted in accordance with Section 245 of the
General Corporation Law of the State of Delaware shall read in its entirety as
follows:

              AMENDED AND RESTATED CERTIFICATE OF INCORPORATION OF
                             BTU INTERNATIONAL, INC.

     1. The name of the corporation is BTU International, Inc.

     2. The address of its registered office in the State of Delaware is
Corporation Trust Center No. 1209 Orange Street, in the City of Wilmington,
County of New Castle. The name of its registered agent at such address is The
Corporation Trust Company.

     3. The nature of the business or purposes to be conducted or promoted is to
engage in any lawful act or activity for which corporations may be organized
under the General Corporation Law of Delaware.

     4. The total number of shares of stock which the corporation shall have
authority to issue is thirty million (30,000,000) shares, of which twenty-five
million (25,000,000) shares shall be common stock, $.01 par value and five
million (5,000,000) shares shall be Series Preferred Stock, $1.00 par value (the
"Series Preferred Stock").

     A statement of the designations of the common stock and the powers and
qualifications, limitations or restrictions thereof, is as follows:

A.  CERTAIN TRANSACTIONS.

     The corporation will not, without the separate votes or consents of the
holders of at least two thirds of the outstanding shares of common stock (i)
liquidate, dissolve or enter into any consolidation, merger or other similar
combination; or (ii) convey or sell all or substantially all of the assets or
business of the corporation and its subsidiaries, taken as a whole; PROVIDED,
that the terms of any such transaction which involves the purchase, transfer or
other disposition of the corporation's capital stock or the distribution to the
corporation's shareholders of the proceeds from the voluntary liquidation of the
corporation shall provide that the assets or the aggregate purchase price
produced by any such disposition or liquidation shall be allocated as follows:



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     First, to the holders of common stock, amounts per share of common stock
equal to $5.00; and

     Second, to the holders of common stock, the entire balance of such assets
or purchase price in amounts per share equal to such balance divided by the
aggregate number of outstanding shares of common stock.

B.  PREEMPTIVE RIGHTS.

     The corporation hereby agrees that it shall not issue any shares of common
stock or warrants, options or other rights to purchase such shares or any
securities convertible into or exchangeable for such shares (for purposes of
this paragraph C, all such shares, warrants, options, other rights and
convertible or exchangeable securities are collectively referred to as
"securities") except as follows:

          (i)   As a dividend, stock split, reclassification, distribution or
                similar issuance of securities payable pro rata to all
                holders of common stock.

          (ii)  To be issued to employees or consultants of the corporation
                pursuant to equity incentive programs of the corporation
                from time to time.

          (iii) In connection with a merger by the corporation with, or
                acquisition by the corporation of, another corporation as
                may be approved by the holders of the requisite majority of
                the then outstanding voting stock of the corporation as
                required by applicable law and by the certificate of
                incorporation and By-laws of the corporation.

          (iv)  In connection with any public offering of the corporation's
                capital stock under the Securities Act of 1933 (or successor
                legislation).

          (v)   For cash or other consideration (other than as described in
                subparagraphs (ii), (iii) and (iv) above).

C. VOTING RIGHTS.

          (i)   Except as otherwise provided by the law of Delaware or in this
                paragraph D, the entire voting power for the election of
                directors of the corporation and for all other purposes
                shall be vested in the holders of common stock with the
                holder of each share of common stock being entitled to one
                vote in respect of such share of common stock.

     5. Subject to the limitations prescribed by law and the provisions of this
Restated Certificate of Incorporation, the board of directors of the corporation
is authorized to provide for the issuance from time to time of shares of the
Series Preferred Stock in one or more series and, by filing a certificate
pursuant to the Delaware General Corporation Law, to establish from time to time
the number of shares to be included in each series and to fix and determine with
respect

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to each series the designations, preferences, powers and relative,
participating, optional or other special rights, and the qualifications,
limitations or restrictions thereof, to the full extent now or hereafter
permitted by law. All shares of any one series of Series Preferred Stock shall
be identical in all respects, except that shares of any one series issued on
different dates may differ as to dates, if any, from which dividends thereon are
to accrue and/or accumulate.

     6. The corporation is to have perpetual existence.

     7. A director of this corporation shall not be liable to the corporation or
its stockholders for monetary damages for breach of fiduciary duty as a
director, except to the extent that exculpation from liability is not permitted
under the Delaware General Corporation Law as in effect at the time such
liability is determined. No amendment or repeal of this article 7 shall apply to
or have any effect on the liability of any director of the corporation for or
with respect to any acts or omissions of such director occurring prior to such
amendment or repeal.

     8. In furtherance and not in limitation of the powers conferred by statute,
the board of directors is expressly authorized to make, alter or repeal the
by-laws of the corporation.

     9. Elections of directors need not be by written ballot unless the by-laws
may provide. The books of the corporation may be kept (subject to any provision
contained in the statutes) outside the State of Delaware at such place or places
as may be designated from time to time by the board of directors or in the
by-laws of the corporation.

     10. Any action by the holders of the Common Stock must be taken at an
annual or special meeting of stockholders and may not be taken by written
consent.

     11. The corporation reserves the right to amend, alter, change or repeal
any provision contained in this restated certificate of incorporation, in the
manner now or hereafter prescribed by statute, and all rights conferred upon
stockholders herein are granted subject to this reservation.

     (c) The board of directors by unanimous vote on April 1, 2001, duly adopted
resolutions proposing an Amended and Restated Certificate of Incorporation of
such corporation as set forth above, declaring such amendment and restatement to
be advisable and calling for a special meeting of the stockholders of such
corporation for consideration thereof or for a consent of the requisite
stockholders in lieu thereof.

     (d) Thereafter, pursuant to the resolution of the board of directors, the
stockholders of such corporation duly adopted the proposed amendment and
restatement set forth above in accordance with the provisions of Section 242 of
the General Corporation Law of the State of Delaware at an annual meeting of
stockholders. The vote required by the stockholders was a majority of the
outstanding shares of common stock.


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     IN WITNESS WHEREOF, BTU International, Inc. has caused this certificate to
be signed by its President and Chief Executive Officer, Paul J. van der Wansem,
and attested by its Secretary, John E. Beard, this 19th day of June, 2001.


                                             BTU INTERNATIONAL, INC.

                                             By:  /s/ Paul J. van der Wansem
                                                  Paul J. van der Wansem
                                                  President and Chief Executive
                                                  Officer

[Corporate Seal]

ATTEST:

By:  /s/ John E. Beard

         Secretary




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