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                                                                       EXHIBIT 5

               MINTZ, LEVIN, COHN, FERRIS, GLOVSKY AND POPEO, P.C.

                              One Financial Center
                           Boston, Massachusetts 02111


701 Pennsylvania Avenue, N.W.                            Telephone: 617/542-6000
Washington, D.C. 20004                                   Fax: 617/542-2241
Telephone: 202/434-7300                                  www.mintz.com
Fax: 202/434-7400

                                                        February 6, 1998

       Ibis Technology Corporation
       32 Cherry Hill Drive
       Danvers, Massachusetts 01923

       Gentlemen:

               We have acted as counsel to Ibis Technology Corporation, a
       Massachusetts corporation (the "Company"), in connection with the
       preparation and filing with the Securities and Exchange Commission of
       Post-Effective Amendment No. 3 to Form S-1 Registration Statement on Form
       S-3 Registration Statement (the "Registration Statement"), pursuant to
       which the Company is registering under the Securities Act of 1933, as
       amended, an aggregate of 125,280 shares (the "Shares") of its common
       stock, $.008 par value per share (the "Common Stock"), which are issuable
       upon exercise of warrants originally issued to the underwriter of the
       Company's initial public offering, for resale to the public. The Shares
       are to be sold by the selling stockholders identified in the Registration
       Statement (the "Selling Stockholders"). This opinion is being rendered in
       connection with the filing of the Registration Statement. All capitalized
       terms used herein and not otherwise defined shall have the respective
       meanings given to them in the Registration Statement.

               In connection with this opinion, we have examined the Company's
       Restated Articles of Organization and Restated By-Laws, both as currently
       in effect; such other records of the corporate proceedings of the Company
       and certificates of the Company's officers as we have deemed relevant;
       and the Registration Statement and the exhibits thereto.

               In our examination, we have assumed the genuineness of all
       signatures, the legal capacity of natural persons, the authenticity of
       all documents submitted to us as originals, the conformity to original
       documents of all documents submitted to us as certified or photostatic
       copies and the authenticity of the originals of such copies.

               Based upon the foregoing, and subject to the limitations set
       forth below, we are of the opinion that (i) the Shares have been duly and
       validly authorized by the Company and (ii) the Shares, when sold by the
       Selling Stockholders, will have been duly and validly issued, fully paid
       and non-assessable shares of the Common Stock.

               Our opinion is limited to the laws of the Commonwealth of
       Massachusetts, and we express no opinion with respect to the laws of any
       other jurisdiction. No opinion is expressed herein with respect to the
       qualification of the Shares under the securities or blue sky laws of any
       state or any foreign jurisdiction.



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Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

Ibis Technology Corporation
February 6, 1998
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               We understand that you wish to file this opinion as an exhibit to
       the Registration Statement, and we hereby consent thereto. We hereby
       further consent to the reference to us under the caption "Legality of
       Common Stock" in the prospectus included in the Registration Statement.


                                                 Very truly yours,

                                                 /s/ Mintz, Levin, Cohn, Ferris,
                                                     Glovsky and Popeo, P.C.
                                                 -------------------------------

                                                 Mintz, Levin, Cohn, Ferris,
                                                   Glovsky and Popeo, P.C.