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                                                                    EXHIBIT 10.5



PAGES WHERE CONFIDENTIAL TREATMENT HAS BEEN GRANTED ARE STAMPED "CONFIDENTIAL
TREATMENT GRANTED," AND THE CONFIDENTIAL SECTION HAS BEEN MARKED IN THE MARGIN
WITH A STAR(*).


                               IMMUNITY AGREEMENT

     THIS AGREEMENT is effective as of the 18th day of October, 1996, by and
     between MOTOROLA, INC., a Delaware corporation having an office at 3102
     North 56th Street, Phoenix, Arizona 85018. (hereinafter called
     "MOTOROLA"), and ST ASSEMBLY TEST SERVICES PTE. LTD. having its principal
     office at 33 Marsiling Industrial Estate Road 3, #03-01, Singapore 739256,
     (hereinafter called "ASSEMBLY HOUSE").

     WHEREAS, MOTOROLA owns and has, or may have patents issued and applications
     for patents pending in various countries of the world which relate to ball
     grid array (BGA) PACKAGEs (as hereinafter defined), and

     WHEREAS, ASSEMBLY HOUSE owns and has, or may have rights in various
     patents issued and applications for patents pending in various countries of
     the world which may relate to BGA PACKAGEs, and

     WHEREAS, ASSEMBLY HOUSE and MOTOROLA are engaged in continuing research,
     development and engineering in regard to BGA PACKAGES and have programs for
     the patenting of inventions resulting therefrom; and

     WHEREAS, MOTOROLA is interested in proliferating BGA PACKAGEs as a standard
     in the semiconductor industry; and

     WHEREAS, ASSEMBLY HOUSE is interested in providing the service of making
     BGA PACKAGEs for semiconductor manufacturers including those who are
     competitors of MOTOROLA;

     NOW THEREFORE, in consideration of the mutual covenants and conditions
     hereinafter setforth, it is agreed as follows:

     Section 1 - DEFINITIONS

     1.1  SUBSIDIARY(IES) means a corporation, company, or other entity more
          than fifty percent (50%) of whose outstanding shares or securities
          (representing the right to vote for the election of directors or
          other managing authority) are, now or hereafter, owned or controlled,
          directly or indirectly by a party hereto, but such corporation,
          company, or other entity shall be deemed to be a SUBSIDIARY only so
          long as such ownership or control exists.

     1.2  SEMICONDUCTIVE MATERIAL means any material whose conductivity is
          intermediate to that of metals and insulators at room temperature
          and whose conductivity, over some temperature range, increases with
          increases in temperature. Such material shall include but not be
          limited to refined products, reaction products, reduced products,
          mixtures and compounds.

     1.3  INTEGRATED CIRCUIT STRUCTURE means an integral unit consisting
          primarily of a plurality of active and/or passive circuit elements
          associated on, or in, a unitary body of SEMICONDUCTIVE MATERIAL for
          performing electrical or electronic functions.

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1.4  BGA PACKAGE means a housing for an INTEGRATED CIRCUIT STRUCTURE or
     STRUCTUREs in which the INTEGRATED CIRCUIT STRUCTURE or STRUCTUREs are
     mounted on one side of a substrate of printed circuit board material or
     the like and are wire bonded to the substrate, plastic overlies the
     INTEGRATED CIRCUIT STRUCTURE or STRUCTUREs, and pads for receiving solder
     balls or the like and providing electrical contacts to the integrated
     circuit device are mounted on the substrate on the side opposite to that
     on which the INTEGRATED CIRCUIT STRUCTURE or STRUCTUREs are mounted. Some
     BGA packages may have some pads which are not electrically connected to
     the INTEGRATED CIRCUIT STRUCTURE or STRUCTUREs.

1.5  MOTOROLA PATENTS means all classes or types of patents, utility models,
     design patents and applications for the aforementioned of all countries of
     the world relating to BGA PACKAGEs and enhancements thereto which, prior
     to the date of expiration or termination of this Agreement, are:

     (i)  issued, published or filed and which arises out of inventions made
          solely by one or more employees of MOTOROLA or a SUBSIDIARY thereof,
          or

     (ii) acquired by MOTOROLA or a SUBSIDIARY thereof.

     and under which and to the extent to which and subject to the conditions
     under which MOTOROLA or a SUBSIDIARY thereof may have, as of the EFFECTIVE
     DATE of this Agreement, or may thereafter during the term of this
     Agreement acquire, the right to grant licenses or rights of the scope
     granted herein without the payment of royalties or other consideration to
     third persons, except for payments to third persons (a) for inventions
     made by said third persons while engaged by MOTOROLA or a SUBSIDIARY
     thereof, and (b) as consideration for the acquisition of such patents,
     utility models, design parents and applications.

1.6  ASSEMBLY HOUSE PATENTS means all classes or types of patents, utility
     models, design patents and applications for the aforementioned of all
     countries of the world relating to BGA PACKAGEs and enhancements thereto
     which, prior to the date of expiration or termination of this Agreement,
     are:

     (i)  issued, published or filed, and which arise out of inventions made
          solely by one or more employees of ASSEMBLY HOUSE or a SUBSIDIARY
          thereof, or

     (ii) acquired by ASSEMBLY HOUSE or a SUBSIDIARY thereof,

     and under which and to the extent to which and subject to the conditions
     under which ASSEMBLY HOUSE or a SUBSIDIARY thereof may have, as of the
     EFFECTIVE DATE of this Agreement, or may thereafter during the term of
     this Agreement acquire, the right to grant licenses or rights of the scope
     granted herein without the payment of royalties or other consideration to
     third persons, except for payments to third persons (a) for inventions
     made by said third persons while engaged by ASSEMBLY HOUSE or a SUBSIDIARY
     thereof and (b) as consideration for the acquisition of such patents,
     utility models, design patents and applications.

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*CONFIDENTIAL TREATMENT GRANTED.


     1.7  EFFECTIVE DATE means the date of the last signature hereto.

     Section 2 - MUTUAL RELEASES

     2.1  MOTOROLA hereby releases, acquits and forever discharges ASSEMBLY
          HOUSE and its SUBSIDIARIES for any time prior to the EFFECTIVE DATE,
          from any and all claims or liability for infringement or alleged
          infringement of any MOTOROLA PATENTS for which immunity from suit is
          herein granted by MOTOROLA.

     2.2  ASSEMBLY HOUSE and its SUBSIDIARIES hereby releases, acquits and
          forever discharges MOTOROLA and its SUBSIDIARIES for any time prior
          to the EFFECTIVE DATE, from any and all claims or liability for
          infringement or alleged infringement of any ASSEMBLY HOUSE PATENTS
          for which immunity from suit is herein granted by ASSEMBLY HOUSE to
          MOTOROLA.

     Section 3 - IMMUNITY FROM SUIT

     3.1  MOTOROLA hereby grants to ASSEMBLY HOUSE and its SUBSIDIARIES, for
          the term of this Agreement, immunity from suit under MOTOROLA PATENTS
          for making BGA PACKAGES, with or without solder balls or the like, for
          another and for ASSEMBLY HOUSE internal use. In no event shall the
          immunity from suit apply to MOTOROLA PATENTS which are infringed by
          the INTEGRATED CIRCUIT STRUCTURE or STRUCTUREs independent of being
          packaged in BGA PACKAGES.

     3.2  ASSEMBLY HOUSE and its SUBSIDIARIES hereby grant to MOTOROLA and its
          SUBSIDIARIES, for the term of this Agreement, immunity from suit under
          ASSEMBLY HOUSE PATENTS for making and/or having made BGA PACKAGES,
          with or without solder balls or the like, and for the subsequent sale
          and use thereof. In no event shall the immunity from suit apply to
          ASSEMBLY HOUSE PATENTS which are infringed by the INTEGRATED CIRCUIT
          STRUCTURE or STRUCTUREs independent of being packaged in BGA PACKAGEs.

     3.3  No licenses under any copyrights or mask work rights of either
          MOTOROLA or ASSEMBLY HOUSE or a SUBSIDIARY thereof, are granted under
          this Agreement.

     Section 4 - PAYMENTS

     4.1  In partial consideration of the rights granted by MOTOROLA under
          Section 3, for the period beginning on the EFFECTIVE DATE and
          extending to December 31, 2002, ASSEMBLY HOUSE agrees to pay MOTOROLA
          a royalty based on the total number of pads on BGA PACKAGEs made by
          ASSEMBLY HOUSE and its SUBSIDIARIES, and shipped and invoiced to
          customers of ASSEMBLY HOUSE or its SUBSIDIARIES, excluding those made
          for MOTOROLA and excluding returns.

*         4.1.1     The royalty shall be *** per *** until a royalty of *** has
                    been accrued.

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*CONFIDENTIAL TREATMENT GRANTED.


*         4.12 After a royalty of *** has been accrued, the royalty shall be
               *** per pad.

     4.2  Royalty payments shall be determined by the total number of pads on
          BGA PACKAGEs subject to the immunity from suit of section 3.1
          shipped during a payment period to customers of ASSEMBLY HOUSE or
          its  SUBSIDIARIES excluding those shipped to MOTOROLA and excluding
          returns.

     4.3  Payment periods shall be on a quarterly basis. Within forty-five (45)
          days after each calendar quarter ending March 31, June 30,
          September 30, and December 31. ASSEMBLY HOUSE shall pay to MOTOROLA
          the royalties payable hereunder for the respective calendar
          quarter ending on such date as determined above.

     4.4  Any payment hereunder which shall be delayed for more than thirty
          (30) days beyond the due date shall be subject to an interest
          charge of one (1) percent per month on the unpaid balance payable
          in United States currency until paid. The foregoing payment of
          interest shall not affect MOTOROLA's right to terminate in
          accordance with Section 5.

     4.5  ASSEMBLY HOUSE shall keep full, clear and accurate records with
          respect to BGA PACKAGEs. MOTOROLA shall have the right through a
          mutually agreed upon independent auditor to examine and audit no
          more than once a year at a mutually agreeable time all such records
          and such other records and accounts as may under recognized
          accounting practices contain information bearing upon the amount
          of royalty payable to MOTOROLA under this Agreement. Prompt
          adjustment shall be made to compensate for any errors or omissions
          disclosed by such examination or audit. Neither such right to
          examine and audit nor the right to receive such adjustment shall
          be affected by any statement to the contrary appearing on a check
          or otherwise. MOTOROLA shall be responsible for the compensation
          of the auditor.

     4.6  Within forty-five (45) days after each calendar quarter ending
          March 31, June 30, September 30, December 31 and continuing
          thereafter until all royalties payable hereunder shall have been
          reported and paid, ASSEMBLY HOUSE shall furnish to MOTOROLA a
          detailed and complete written statement, certified by a
          responsible officer of ASSEMBLY HOUSE as showing all BGA PACKAGEs
          which were either manufactured, sold, leased, put into use, or
          otherwise disposed of during such periods, and the amount payable
          thereon. If no such BGA PACKAGEs have been manufactured, sold,
          leased, put into use, or otherwise disposed of, that fact shall
          be shown on such statement.

     4.7  Payments hereunder are to be made to MOTOROLA's New York City
          account at CITIBANK 38491386, 1 Citicorp Center, 399 Park Avenue,
          New York,   New York 10043. Notice of payments shall be sent by
          ASSEMBLY HOUSE  to MOTOROLA's address in Section 6.9.

     Section 5 - TERM AND TERMINATION AND ASSIGNABILITY

     5.1  The term of this Agreement shall be from the EFFECTIVE DATE until
          December 31, 2002 unless earlier terminated as elsewhere provided
          in this Agreement.

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5.2  In the event of any breach of this Agreement by either party hereto
     (including ASSEMBLY HOUSE's obligation to make payments under Section 4),
     if such breach is not corrected within forty-five (45) days after written
     notice describing such breach, this Agreement may be terminated forthwith
     by further written notice to that effect from the party noticing the
     breach.

5.3  Either party hereto shall also have the right to terminate this Agreement
     forthwith by giving written notice of termination to the other party at
     any time, upon or after:

     5.3.1  the filing by such other party of a petition in bankruptcy or
            insolvency; or

     5.3.2  any adjudication that such other party is bankrupt or insolvent; or

     5.3.3  the filing by such other party of any legal action or document
            seeking reorganization, readjustment or arrangement of its business
            under any law relating to bankruptcy or insolvency; or

     5.3.4  the appointment of a receiver for all or substantially all of the
            property of such other party; or

     5.3.5  the making by such other party of any assignment for the benefit of
            creditors; or

     5.3.6  the institution of any proceedings for the liquidation or winding
            up of such other party's business or for the termination of its
            corporate charter.

5.4  In the event of termination of this Agreement by one party pursuant to
     Section 5.2, the immunity and rights granted to or for the benefit of that
     one party hereto and its SUBSIDIARIES under MOTOROLA PATENTS or ASSEMBLY
     HOUSE PATENTS, as the case may be, depending upon who is the party doing
     the terminating, shall survive such termination and shall extend for the
     full term of this Agreement, but the immunity and rights granted to or for
     the benefit of the other party shall terminate as of the date termination
     takes effect.

5.5  At such time as is mutually agreeable, at the written request of either
     party hereto to the other party hereto, but in no event less than six (6)
     months prior to the expiration of this Agreement, the parties hereto shall
     discuss the possible extension of or the renewal of the term of this
     Agreement, including the possible amendment of the provisions thereof.

5.6  The rights or privileges provided for in this Agreement may be assigned or
     transferred by either party only with the prior written consent of the
     other party and with the authorization or approval of any governmental
     authority as then may be required, except to a successor in ownership of
     all or substantially all of the assets of the assigning party. Such
     successor, before such assignment or transfer is effective, shall
     expressly assume in writing to the other party the performance of all of
     the terms and conditions of this Agreement to be performed by the
     assigning party.

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     Section 6 - MISCELLANEOUS PROVISIONS

     6.1  Each of the parties hereto represents and warrants that it has
          the right to grant to or for the benefit of the other the
          immunity and rights granted hereunder in Sections 2 and 3.

     6.2  Nothing contained in this Agreement shall be construed as:

          6.2.1  restricting the right of MOTOROLA or any of its
                 SUBSIDIARIES to make, use, sell, lease or otherwise
                 dispose of any particular product or products not
                 herein licensed;

          6.2.2  restricting the right of ASSEMBLY HOUSE or any of its
                 SUBSIDIARIES to make, use, sell, lease or otherwise
                 dispose of any particular product or products not
                 herein licensed;

          6.2.3  an admission by ASSEMBLY HOUSE of, or a warranty or
                 representation by MOTOROLA as to, the validity and/or
                 scope of the MOTOROLA PATENTS, or a limitation on
                 ASSEMBLY HOUSE to contest, in any proceeding, the
                 validity and/or scope thereof;

          6.2.4  an admission by MOTOROLA of, or a warranty or
                 representation by ASSEMBLY HOUSE as to, the validity
                 and/or scope of the ASSEMBLY HOUSE PATENTS, or a
                 limitation on MOTOROLA to contest, in any proceeding,
                 the validity and/or scope thereof;

          6.2.5  conferring any license or other right, by implication,
                 estoppel or otherwise, under any patent application,
                 patent or patent right, except as herein expressly
                 granted under the MOTOROLA PATENTS and the ASSEMBLY
                 HOUSE PATENTS;

          6.2.6  conferring any license or right with respect to any
                 trademark, trade or brand name, a corporate name of
                 either party or any of their respective SUBSIDIARIES, or
                 any other name or mark or contraction, abbreviation or
                 simulation thereof;

          6.2.7  imposing on MOTOROLA any obligation to institute any
                 suit or action for infringement of any MOTOROLA PATENTS,
                 or to defend any suit or action brought by a third party
                 which challenges or concerns the validity of any
                 MOTOROLA PATENTS;

          6.2.8  imposing upon ASSEMBLY HOUSE any obligation to institute
                 any suit or action for infringement of any ASSEMBLY HOUSE
                 PATENTS, or to defend any suit or action brought by a third
                 party which challenges or concerns the validity of any
                 ASSEMBLY HOUSE PATENTS;

          6.2.9  imposing on either party any obligation to file any patent
                 application or to secure any patent or maintain any patent
                 in force; or

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          6.2.10  an obligation on either party to furnish any manufacturing
                  or technical information under this Agreement except as the
                  same is specifically provided for herein.

     6.3  No express or implied waiver by either of the parties to this Agree-
          ment of any breach of any term, condition or obligation of this
          Agreement by the other party shall be construed as a waiver of any
          subsequent breach of that term, condition or obligation or of any
          other term, condition or obligation of this Agreement of the same or
          of a different nature.

     6.4  Anything contained in this Agreement to the contrary notwithstanding,
          the obligations of the parties hereto shall be subject to all laws,
          both present and future, of any Government having jurisdiction over
          either party hereto, and to orders or regulations of any such
          Government, or any department, agency, or court thereof, and acts of
          war, acts of public enemies, strikes, or other labor disturbances,
          fires, floods, acts of God, or any causes of like or different kind
          beyond the control of the parties, and the parties hereto shall be
          excused from any failure to perform any obligation hereunder to the
          extent such failure is caused by any such law, order, regulation, or
          contingency but only so long as said law, order, regulation or contin-
          gency continues.

     6.5  The captions used in this Agreement are for convenience only and are
          not to be used in interpreting the obligations of the parties under
          this Agreement.

     6.6  This Agreement and the performance of the parties hereunder shall be
          construed in accordance with and governed by the laws of the State of
          Illinois.

     6.7  If any term, clause, or provision of this Agreement shall be judged
          to be invalid, the validity of any other term, clause, or provision
          shall not be affected; and such invalid term, clause, or provision
          shall be deemed deleted from this Agreement.

     6.8  This Agreement sets forth the entire Agreement and understanding
          between the parties as to the subject matter hereof and merges all
          prior discussions between them, and neither of the parties shall be
          bound by any conditions, definitions, warranties, understandings or
          representations with respect to such subject matter other than as
          expressly provided herein or as duly set forth on or subsequent to
          the date hereof in writing and signed by a proper and duly authorized
          officer or representative of the party to be bound thereby.

     6.9  All notices required or permitted to be given hereunder shall be in
          writing and shall be valid and sufficient if dispatched by registered
          airmail, postage prepaid, in any post office in the United States,
          addressed as follows:

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          6.9.1     If to MOTOROLA:

                    Motorola Inc.
                    1303 East Algonquin Road
                    Schaumburg, Illinois 60196

                    Attention: Vice President for Patents, Trademarks &
                               Licensing

          6.9.2     If to ASSEMBLY HOUSE:

                    ST Assembly Test Services Pte. Ltd.
                    33 Marsiling Industrial Estate Road 3
                    #03-01
                    Singapore 739256

                    Attention: Mr. Lee Joon Chung, General Manager

          6.9.3     The date of receipt of such a notice shall be the date for
                    the commencement of the running of the period provided for
                    in such notice, or the date at which such notice takes
                    effect as the case may be.

          IN WITNESS WHEREOF, the parties hereto have executed this Agreement
          in duplicate.


          <TABLE>
          <CAPTION>

          <S>                                   <C>
          MOTOROLA INC.                         ST ASSEMBLY TEST SERVICES PTE. LTD.

          /s/ GEORGE TURNER                     /s/ LEE JOON CHUNG
          ----------------------                ------------------------------
          George Turner                         Mr. Lee Joon Chung
          Vice President & General Manager      General Manager
          Logic and Analog Technologies Group   ST Assembly Test Services Pte. Ltd.
          Semiconductor Products Sector
          Motorola, Inc.

          Date: 9/30/96                         Date: 9/11/96
                -------                               -------


          /s/ JAMES W. GILLMAN                  /s/ TAN BOCK SENG
          ----------------------                ------------------------------
          James W. Gillman                      Mr. Tan Bock Seng
          Corporate Vice President, Patents     Board Director
          Trademarks, and Licensing             ST Assembly Test Services Pte. Ltd.
          Motorola, Inc.

          Date: 10/18/96                        Date: 9/11/96
                --------                              -------

</TABLE>

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