Exhibit 31.1
Section 302 Certification by Chief Executive Officer of Quarterly Report


                            CERTIFICATION PURSUANT TO
                             18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                SECTION 302 (a) OF THE SARBANES-OXLEY ACT OF 2002


I,  Patrick  J.  Brockett,  President  and Chief  Executive  Officer  of Zarlink
Semiconductor Inc., certify that:

      1.    I have  reviewed  this  quarterly  report  on Form  10-Q of  Zarlink
            Semiconductor Inc. (the "registrant");

      2.    Based on my  knowledge,  this  report  does not  contain  any untrue
            statement  of a  material  fact  or omit to  state a  material  fact
            necessary to make the statements made, in light of the circumstances
            under which such  statements  were made, not misleading with respect
            to the period covered by this report;

      3.    Based on my knowledge, the financial statements, and other financial
            information included in this report,  fairly present in all material
            respects the financial  condition,  results of  operations  and cash
            flows of the  registrant  as of, and for,  the periods  presented in
            this report;

      4.    The registrant's  other certifying officer and I are responsible for
            establishing and maintaining  disclosure controls and procedures (as
            defined in  Exchange  Act Rules  13a-15(e)  and  15d-15(e))  for the
            registrant and have:

            a)    Designed such disclosure  controls and  procedures,  or caused
                  such  disclosure  controls and procedures to be designed under
                  our supervision,  to ensure that material information relating
                  to the registrant, including its consolidated subsidiaries, is
                  made known to us by others within those entities, particularly
                  during the period in which this report is being prepared;

            b)    Evaluated the  effectiveness  of the  registrant's  disclosure
                  controls  and  procedures  and  presented  in this  report our
                  conclusions about the effectiveness of the disclosure controls
                  and  procedures  as of the end of the  period  covered by this
                  report based on such evaluation; and

            c)    Disclosed  in  this  report  any  change  in the  registrant's
                  internal control over financial reporting that occurred during
                  the registrant's  most recent fiscal quarter (the registrant's
                  fourth  fiscal  quarter in the case of an annual  report) that
                  has materially affected, or is reasonably likely to materially
                  affect,  the  registrant's  internal  control  over  financial
                  reporting; and

      5.    The  registrant's  other  certifying  officer and I have  disclosed,
            based  on our  most  recent  evaluation  of  internal  control  over
            financial  reporting,  to the  registrant's  auditors  and the audit
            committee of registrant's  board of directors (or persons performing
            the equivalent function):

            a)    All significant  deficiencies  and material  weaknesses in the
                  design  or  operation  of  internal  controls  over  financial
                  reporting which are reasonably  likely to adversely affect the
                  registrant's ability to record, process,  summarize and report
                  financial information; and

            b)    Any fraud,  whether or not material,  that involves management
                  or  other  employees  who  have  a  significant  role  in  the
                  registrant's internal control over financial reporting.



            Date:        July 23, 2004
                 ---------------------------------

                                          /s/ PATRICK J. BROCKETT
                                          --------------------------------------
                                          Patrick J. Brockett
                                          President and Chief Executive Officer