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EXHIBIT 5.1
[MORRISON & FOERSTER LLP LETTERHEAD]
December 8, 2000
Novellus Systems, Inc.
4000 North First Street
San Jose, CA 95134
Ladies and Gentlemen:
At your request, we have examined the Registration Statement on Form S-4,
including the proxy statement-prospectus forming a part thereof, filed by you
with the Securities and Exchange Commission on November 20, 2000 and
subsequently to be amended (the "Registration Statement"), in connection with
the registration under the Securities Act of 1933, as amended, of 9,750,589
shares of your common stock, no par value per share (the "Stock"). The Stock
will be issued to the former stockholders of GaSonics International Corporation
("GaSonics"), a Delaware corporation, pursuant to the terms of that certain
Agreement and Plan of Reorganization, dated as of October 25, 2000, by and among
you, Neptune Acquisition-Sub, Inc. a Delaware corporation and your wholly-owned
subsidiary, and GaSonics (the "Reorganization Agreement"). As counsel to the
Company and in connection with this opinion, we have examined all proceedings
taken by you in connection with the registration of the Stock.
It is our opinion that the Stock, which is being issued by you in exchange
for the shares of common stock of GaSonics pursuant to the Reorganization
Agreement, when issued in the manner described in the Registration Statement
will be legally and validly issued, fully paid and nonassessable.
We consent to the use of this opinion as an exhibit to the Registration
Statement and further consent to all references to us in the Registration
Statement and any amendments thereto. In giving this consent, we do not thereby
admit that we are in the category of persons whose consent is required under
Section 7 of the Securities Act of 1933, as amended.
Very truly yours,
/s/ Morrison & Foerster LLP
