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                                                                     EXHIBIT 3.1


                                    RESTATED

                          CERTIFICATE OF INCORPORATION

                                       OF

                         AMERICAN XTAL TECHNOLOGY, INC.



     AMERICAN XTAL TECHNOLOGY, INC., a corporation organized and existing under
the laws of the State of Delaware, hereby certifies as follows:

     1.   The name of the corporation is American Xtal Technology, Inc.

     2.   The original name of the corporation was American Xtal Technology
Delaware Corporation.

     3.   The date of filing of its original Certificate of Incorporation with
the Secretary of State of the State of Delaware was November 13, 1997.

     4.   This Restated Certificate of Incorporation was duly adopted in
accordance with the provisions of Section 245 of the Delaware General
Corporation Law. This Restated Certificate of Incorporation only restates and
integrates and does not further amend the provisions of the corporation's
certificate of incorporation as heretofore amended, and there is no discrepancy
between those provisions and the provisions of this Restated Certificate of
Incorporation.

     5.   This Restated Certificate of Incorporation restates and integrates the
Certificate of Incorporation of this corporation as herein set forth in full:


     FIRST:    The name of the corporation is American Xtal Technology, Inc.
               (hereinafter sometimes referred to as the "Corporation").   

     SECOND:   The address of the registered office of the Corporation in the
               State of Delaware is Incorporating Services, Ltd., 15 East North
               Street, in the City of Dover, County of Kent. The name of the
               registered agent at that address is Incorporating Services, Ltd.

     THIRD:    The purpose of the Corporation is to engage in any lawful act or
               activity for which a corporation may be organized under the
               General Corporation Law of Delaware.

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     FOURTH:
                                            STOCK

               The Corporation is authorized to issue two classes of stock to be
               designated, respectively, "Preferred Stock" and "Common Stock."
               The total number of shares of Preferred Stock the Corporation
               shall have authority to issue is 2,000,000, $.001 par value per
               share, and the total number of shares of Common Stock the
               Corporation shall have authority to issue is 40,000,000, $0.001
               par value per share. The shares of Preferred Stock shall
               initially be undesignated as to series.

               The Board of Directors is hereby authorized, within the
               limitations and restrictions stated herein, to determine or alter
               the rights, preferences, privileges and restrictions granted to
               or imposed upon a wholly unissued series of Preferred Stock, and
               the number of shares constituting any such series and the
               designation thereof, or any of them; and to increase or decrease
               the number of shares constituting any such series and the
               designation thereof, or any of them; and to increase or decrease
               the number of shares of any series subsequent to the issue of
               shares of that series, but, in respect of decreases, not below
               the number of shares of such series then outstanding. If the
               number of shares of any such series of Preferred Stock shall be
               so decreased, the shares constituting such decrease shall be
               retired and shall not be reissued by the Corporation.

     FIFTH:    The following provisions are inserted for the management of the
               business and the conduct of the affairs of the Corporation, and
               for further definition, limitation and regulation of the powers
               of the Corporation and of its directors and stockholders:

          A.   The business and affairs of the Corporation shall be managed by
               or under the direction of the Board of Directors. In addition to
               the powers and authority expressly conferred upon them by statute
               or by this Certificate of Incorporation or the Bylaws of the
               Corporation, the directors are hereby empowered to exercise all
               such powers and do all such acts and things as may be exercised
               or done by the Corporation.

          B.   The directors of the Corporation need not be elected by written
               ballot unless the Bylaws so provide.

          C.   Any action required or permitted to be taken by the stockholders
               of the Corporation must be effected at a duly called annual or
               special meeting of stockholders of the Corporation and may not be
               effected by any consent in writing by such stockholders.

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          D.   Special meetings of stockholders of the Corporation may be called
               only (1) by the Board of Directors pursuant to a resolution
               adopted by a majority of the total number of authorized directors
               (whether or not there exist any vacancies in previously
               authorized directorships at the time any such resolution is
               presented to the Board for adoption) or (2) by the holders of not
               less than ten percent (10%) of all of the shares entitled to cast
               votes at the meeting.

     SIXTH:

          A.   The number of directors shall initially be set at five (5) and,
               thereafter, shall be fixed from time to time exclusively by the
               Board of Directors pursuant to a resolution adopted by a majority
               of the total number of authorized directors (whether or not there
               exist any vacancies in previously authorized directorships at the
               time any such resolution is presented to the Board for adoption).
               The directors shall be divided into three classes with the term
               of office of the first class (Class I) to expire at the first
               annual meeting of the stockholders; the term of office of the
               second class (Class II) to expire at the second annual meeting of
               stockholders; the term of office of the third class (Class III)
               to expire at the third annual meeting of stockholders; and
               thereafter for each such term to expire at each third succeeding
               annual meeting of stockholders after such election. Subject to
               the rights of the holders of any series of Preferred Stock then
               outstanding, a vacancy resulting from the removal of a director
               by the stockholders as provided in Article SIXTH, Section C below
               may be filled at a special meeting of the stockholders held for
               that purpose. All directors shall hold office until the
               expiration of the term for which elected, and until their
               respective successors are elected, except in the case of the
               death, resignation, or removal of any director.

          B.   Subject to the rights of the holders of any series of Preferred
               Stock then outstanding, newly created directorships resulting
               from any increase in the authorized number of directors or any
               vacancies in the Board of Directors resulting from death,
               resignation or other cause (other than removal from office by a
               vote of the stockholders) may be filled only by a majority vote
               of the directors then in office, though less than a quorum, and
               directors so chosen shall hold office for a term expiring at the
               next annual meeting of stockholders at which the term of office
               of the class to which they have been elected expires, and until
               their respective successors are elected, except in the case of
               the death, resignation, or removal of any director. No decrease
               in the number of directors constituting the Board of Directors
               shall shorten the term of any incumbent director.

          C.   Subject to the rights of the holders of any series of Preferred
               Stock then outstanding, any directors, or the entire Board of
               Directors, may be 

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               removed from office at any time, with or without cause, but only
               by the affirmative vote of the holders of at least a majority of
               the voting power of all of the then outstanding shares of capital
               stock of the Corporation entitled to vote generally in the
               election of directors, voting together as a single class.
               Vacancies in the Board of Directors resulting from such removal
               may be filled by a majority of the directors then in office,
               though less than a quorum, or by the stockholders as provided in
               Article SIXTH, Section A above. Directors so chosen shall hold
               office for a term expiring at the next annual meeting of
               stockholders at which the term of office of the class to which
               they have been elected expires, and until their respective
               successors are elected, except in the case of the death,
               resignation, or removal of any director.

     SEVENTH:  The Board of Directors is expressly empowered to adopt, amend or
               repeal Bylaws of the Corporation. Any adoption, amendment or
               repeal of Bylaws of the Corporation by the Board of Directors
               shall require the approval of a majority of the total number of
               authorized directors (whether or not there exist any vacancies in
               previously authorized directorships at the time any resolution
               providing for adoption, amendment or repeal is presented to the
               Board). The stockholders shall also have power to adopt, amend or
               repeal the Bylaws of the Corporation. Any adoption, amendment or
               repeal of Bylaws of the Corporation by the stockholders shall
               require, in addition to any vote of the holders of any class or
               series of stock of the Corporation required by law or by this
               Certificate of Incorporation, the affirmative vote of the holders
               of at least sixty-six and two-thirds percent (66-2/3%) of the
               voting power of all of the then outstanding shares of the capital
               stock of the Corporation entitled to vote generally in the
               election of directors, voting together as a single class.

     EIGHTH:   A director of the Corporation shall not be personally liable to
               the Corporation or its stockholders for monetary damages for
               breach of fiduciary duty as a director, except for liability (i)
               for any breach of the director's duty of loyalty to the
               Corporation or its stockholders, (ii) for acts or omissions not
               in good faith or which involved intentional misconduct or a
               knowing violation of law, (iii) under Section 174 of the Delaware
               General Corporation Law, or (iv) for any transaction from which
               the director derived an improper personal benefit.

               If the Delaware General Corporation Law is hereafter amended to
               authorize the further elimination or limitation of the liability
               of a director, then the liability of a director of the
               Corporation shall be eliminated or limited to the fullest extent
               permitted by the Delaware General Corporation Law, as so amended.

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               Any repeal or modification of the foregoing provisions of this
               Article EIGHTH by the stockholders of the Corporation shall not
               adversely affect any right or protection of a director of the
               Corporation existing at the time of such repeal or modification.

     NINTH:    The Corporation reserves the right to amend or repeal any 
               provision contained in this Certificate of Incorporation in the
               manner prescribed by the laws of the State of Delaware and all
               rights conferred upon stockholders are granted subject to this
               reservation; provided, however, that, notwithstanding any other
               provision of this Certificate of Incorporation or any provision
               of law which might otherwise permit a lesser vote or no vote, but
               in addition to any vote of the holders of any class or series of
               the stock of this Corporation required by law or by this
               Certificate of Incorporation, the affirmative vote of the holders
               of at least 66-2/3% of the voting power of all of the then
               outstanding shares of the capital stock of the Corporation
               entitled to vote generally in the election of directors, voting
               together as a single class, shall be required to amend or repeal
               this Article NINTH, Article FIFTH, Article SIXTH, Article SEVENTH
               or Article EIGHTH.




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     IN WITNESS WHEREOF, this Restated Certificate of Incorporation has been
executed on behalf of the Corporation by Morris S. Young, its President and
Chief Executive Officer and attested by Guy D. Atwood, its Secretary, this 18th
day of June, 1998.


                                       AMERICAN XTAL TECHNOLOGY, INC.




                                       By: /s/ Morris S. Young
                                           --------------------------------
                                           Morris S. Young, President and
                                           Chief Executive Officer


Attest:


By: /s/ Guy D. Atwood
    ---------------------------
    Guy D. Atwood, Secretary


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