Filed by Mattson Technology, Inc. (Commission File No. 000-24838)
                           Pursuant to Rule 425 under the Securities Act of 1933
                                        and deemed filed pursuant to Rule 14a-12
                                          of the Securities Exchange Act of 1934
                                        Subject Company:  CFM Technologies, Inc.
                                                   Commission File No. 000-27498

Press Release

Mattson Merger of STEAG Semiconductor Equipment
Division and CFM Technologies, Inc. Passes Antitrust
Review

HSR Waiting Period Expires and German Federal Cartel Office Approves
Deal

FREMONT, Calif.--(BUSINESS WIRE)--Sept. 14, 2000-- Mattson Technology, Inc.
(Nasdaq:MTSN - news) announced all governmental antitrust notification and
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approval requirements are now satisfied for the proposed business merger between
Mattson and the semiconductor equipment division of STEAG Electronic Systems AG,
and the pending merger with CFM Technologies, Inc. (Nasdaq:CFMT - news). The
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waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976
has expired for both STEAG and CFM Technologies. Mattson also announced that
STEAG received notification that the German Federal Cartel Office has approved
the transactions.

The closing remains subject to approval by the stockholders of Mattson and CFM,
and other customary closing conditions. Mattson plans to file with the SEC a
Proxy Statement/Prospectus relating to the transactions within the next two
weeks. The date for the Mattson and CFM stockholder meetings has not been set,
and will depend upon the time required by any SEC review. A targeted close date
of early January was previously announced. If approvals are obtained early, the
parties plan to accelerate the close date. If closure cannot be accelerated due
to tax and accounting issues, the parties have agreed to waive all other
conditions, essentially fulfilling all terms of the deal except for the passage
of time. This will significantly enhance the certainty of closing the
transaction, meeting the expressed desire of all parties to complete this
transaction as quickly as possible.

About Mattson Technology

Mattson Technology Inc., is a leading supplier of semiconductor process
equipment for photoresist strip/etch, chemical vapor deposition, epitaxial and
rapid thermal processing. The company's products combine advanced process
technology on a high productivity platform, backed by industry-leading support.
Since beginning operations in 1989, the company's core vision has been to help
bring technology leadership and productivity gains to semiconductor
manufacturers worldwide. Headquartered in Fremont, Calif., the company maintains
sales and support centers throughout the United States, Europe, Asia/Pacific and
Japan. For more


information, please contact Mattson Technology Inc., 2800 Bayview Drive,
Fremont, CA 94538. Telephone: 800/MATTSON. Fax: 510/657-0165. Internet:
www.mattson.com.
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This press release contains forward-looking statements regarding, among other
matter, Mattson's future completion of the STEAG and CFM transactions. Forward
looking statements address matters which are subject to a number of risks and
uncertainties, including risks relating to satisfaction of conditions to the
pending acquisitions and risks of integration of the combining businesses and
other factors. Reference is made to the Mattson filings with the Securities and
Exchange Commission for further discussion of risk and uncertainties regarding
the Company's business.

Mattson Technology, Inc. (Mattson) and CFM Technologies, inc. (CFM) will be
filing joint proxy statements / prospectuses and other relevant documents
concerning the proposed business combination and merger with the U.S. Securities
and Exchange Commission (the SEC). Investors are urged to read the proxy
statement / prospectus when it becomes available and any other relevant
documents filed with the SEC because they will contain important information
about the proposed merger. Investors should read the proxy statement /
prospectus before making any voting or investment decisions. Investors will be
able to obtain the documents free of charge at the SEC's website, www.sec.gov,
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and at the SEC public reference rooms in Washington D.C., New York, New York,
and Chicago, Illinois. Please call the sec at 1-800-sec-0330 for more
information on public reference rooms. In addition, documents filed with the SEC
by Mattson may be obtained free of charge by contacting Peter Brown of Mattson
at (800) mattson. Documents filed with the SEC by CFM may be obtained free of
charge by contacting Jeff Randall of CFM at 215/280-8509.

Mattson and its directors and certain of its executive officers may be deemed,
under sec rules, to be soliciting proxies from Mattson's and CFM's stockholders
in favor of the proposed merger. Information regarding the identity of these
persons, and their interests in the solicitation, is set forth in a Schedule 14A
filed with the SEC on July 13, 2000, and available free of charge at the SEC
website and public reference rooms, and from the Mattson contact named above.