[LOGO] ZARLINK                                                      NEWS RELEASE
       SEMICONDUCTOR

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Zarlink Revises Guidance for Second Quarter Fiscal 2004

OTTAWA, CANADA, September 23, 2003 - Zarlink Semiconductor (NYSE/TSX:ZL) today
announced revised guidance for its Fiscal 2004 second quarter, ending September
26, 2003.

      The company now expects revenues of US$47 million, and a net loss of
US$0.15 per share, of which US$0.06 is a non-operating loss related to
restructuring activities announced earlier. In July, Zarlink had projected
revenues of US$51 million and a net loss of approximately US$0.12 per share.

      "The second quarter is seasonally our slowest period, however bookings in
August were significantly lower than anticipated," said Patrick J. Brockett,
President and Chief Executive Officer, Zarlink Semiconductor. "Although we are
experiencing stronger order activity in September, we will not meet our previous
guidance."

      Zarlink will discuss its revised guidance during an open conference call
for analysts, investors and other interested parties, today at 4:30 p.m. EDT.
Please dial 1-800-814-4859 or 613-287-8027. The replay number is 1-877-289-8525
(passcode 21019459#) or 416-640-1917 (passcode 21019459#). The replay will be
available until midnight, Tuesday, October 7, 2003. The call will be webcast
from www.vcall.com (World Investor Link) or via the company's web site at
www.zarlink.com. Media are listen only.

      Zarlink will announce its finalized second quarter results on Thursday,
October 16, 2003 after market close.




About Zarlink Semiconductor

      For almost 30 years, Zarlink Semiconductor has delivered semiconductor
solutions that drive the capabilities of voice, enterprise, broadband and
wireless communications. The company's success is built on its technology
strengths, including voice and data networks, consumer and ultra low-power
communications, and high-performance analog. For more information, visit
www.zarlink.com.

      Certain statements in this press release constitute forward-looking
statements within the meaning of the Private Securities Litigation Reform Act of
1995. Such forward-looking statements involve known and unknown risks,
uncertainties, and other factors which may cause the actual results, performance
or achievements of the Company to be materially different from any future
results, performance, or achievements expressed or implied by such
forward-looking statements. Such risks, uncertainties and assumptions include,
among others, the risks discussed in documents filed by the Company with the
Securities and Exchange Commission. Investors are encouraged to consider the
risks detailed in those filings.

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For further information:
Michael Salter                              Mike McGinn
Corporate Communications                    Investor Relations
613 270-7115                                613 270-7210
michael.salter@zarlink.com                  mike.mcginn@zarlink.com