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                                                                     Exhibit 4.3

                        Investment Cooperation Agreement

This Agreement is entered on December 7, 2003 by and between:

PSi Technologies, Inc. ("PSi"), a corporation registered and existing under the
laws of the Republic of the Philippines, having registered address at
Electronics Ave., FTI Complex, Taguig, Metro Manila, Philippines; and

Management Committee of Chengdu Hi-Tech Zone ("CDHT"), a PRC government entity,
located at 18 Chuangye Road, Chengdu Hi-Tech Zone, Chengdu 610041, Sichuan
Province.

Whereas:

1.   PSi is contemplating an investment ("Investment"), the first phase ("Phase
     No. 1") will commence within three (3) months from the execution of this
     Agreement and the issuance of the Company's Business License, Customs
     permits and other approvals necessary to establish an Assembly and Test
     Facility Factory (the "Company") in Chengdu, Sichuan Province, the Peoples'
     Republic of China;

2.   PSi's Phase No. 1 investment is anticipated to be USD$20 million within
     three years.

3.   In support of the Investment by PSi, CDHT will provide support to PSi, its
     affiliated companies and the Company in accordance with the terms and
     conditions contained herein.

THEREFORE, upon friendly negotiations, the parties hereto reached agreement as
follows:

1.   Lease of Factory and Land

(1)  Factory A and Land A

     i.   Description

          The area of Factory A is 2,592 sqm located on Land A with an area of
          4,117.5 sqm. The property has been installed with seven (7)
          connections such as water, power, gas, drainage, sewage,
          telecommunications, internet and other accessory facilities

     ii.  Lease Terms and Conditions

          a.   The rent of Factory A is RMB8/sqm/month, which shall not be
               changed during the lease term (including any extension of the
               initial lease term). The rent shall be calculated on such basis
               that the area of Factory A is 2,592 sqm. CDHT will not charge any
               rent to the Company for Land A.

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          b.   During the lease term, CDHT will charge a management fee for
               garbage disposal and security services in an amount of
               RMB1/sqm/month. The management fee is calculated on such basis
               that the area of Factory A is 2,592 sqm.

          c.   The term of the lease for Factory A and Land A is 3 years from
               the date on which the lease is to commence.

(2)  Factory B and Land B

     i.   Description

          The area of Factory B is 2,592 sqm located on Land B with an area of
          4,117.5 sqm. The property has been installed with seven (7)
          connections such as water, power, gas, drainage, sewage,
          telecommunications, internet and other accessory facilities

     ii.  Lease Terms and Conditions

          a.   The rent for Factory B is RMB4/sqm/month until the Company
               installs facilities in Factory B. Once the facilities are
               installed in Factory B, the rent shall be increased to
               RMB8/sqm/month. The rent is not subject to any change during the
               term of the lease (including any extension of the initial lease
               term). The rent is calculated based on the area of Factory B of
               2,592 sqm. CDHT will not charge any rent to the Company for Land
               B.

          b.   Once PSi or its affiliated companies or Company installs
               facilities during the lease term, CDHT will charge a management
               fee for garbage disposal and security services equivalent to
               RMB1/sqm/month. The management fee is calculated on such basis
               that the area of Factory B is 2,592 sqm.

          c.   The term of lease for Factory B and Land B is 3 years from the
               date on which the lease is to commence.

(3)  Expansion Land C and D

     i.   Description

          a.   The area of Land C is 17,500 sqm adjacent to Land A and B. The
               area of Land D is 17,500 sqm adjacent to Land C. Both Land C and
               Land D are installed with seven (7) connections, such as water,
               power, gases, drainage, sewage, telecommunications, internet and
               other accessory facilities

          b.   CDHT guarantees that at its own expense, the Land C and D will be
               free and clear of all structures and occupants, that Land C and D
               will be level with Lands A and B, and that the Land C and D will
               be properly compacted so that it is fit to construct a building
               without having to compact the soil further.

          c.   CDHT acknowledges and agrees that at the option of PSi and in
               accordance with the Company's needs, a road may be constructed at
               the expense of CDHT to run through Lands C and D as drawn in the
               site map attached to this Agreement. The Company is entitled to
               exclusive use of the road by fencing and blocking access that
               road.

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     ii.  Purchase

          a.   Within the 3-year term commencing from date on which the lease is
               to begin with respect to Factory A, Land A and Factory B, Land B
               between the Company and the CDHT, the Company has an option to
               purchase the use right to Land C and / or Land D. During the
               above-mentioned 3-year term, the purchase price for the land is
               RMB80/sqm.

          b.   At any time after the 3-year term, the Company has the right of
               first refusal for purchase the use right of Land C and/or Land D
               at the market price. The market price shall be evidenced by a
               formal offer to purchase from a third party.

          c.   The use right to Land C and/or Land D is for a period of not less
               than 50 years.

(4)  General Terms

     i.   The site map of the aforesaid factories and pieces of land ("Factory
          and Land") is attached to this Agreement as Annex A.

     ii.  CDHT hereby guarantees that it has full authorizations, power and
          rights to lease the Factory and Land to the Company and sell the use
          right of the Land. In addition, it has full rights and authorizations
          to represent all and any owner of the factories (if any), or relevant
          governmental authorities in charge of management of real estate and
          land, to execute and deliver this Agreement.

     iii. CDHT guarantees that no litigation, arbitration, disputes or other
          legal administrative procedures is pending or threatening, which is
          related to all the pieces of Land or Factories leased or sold to
          Company. Nor is there any mortgage created in favor of any bank,
          company or person, or lease or any other interest held by any third
          parties attached to the Factories and the Lands.

     iv.  CDHT shall assume and pay all taxes and fees with respect to CDHT's
          acquisition and lease of the use right of every piece of Land.

     v.   CDHT guarantees that every piece of Factory and Land is vacant from
          all and any occupants when the Land is turned over to the Company.
          Should there be any occupant on the Land, CDHT shall clear the land at
          its own cost prior to the start of the lease or effectivity of
          purchase.

     vi.  Unless otherwise expressly provided herein, Company may use the
          Factory and Land freely and legally without any other additional
          charges or taxes, unless in the case of taxes, mandated by future
          government regulation or law.

     vii. All terms and conditions with respect to any lease of factories and
          land to the Company other than those provided herein shall be
          determined by the definitive lease agreement executed by the Company
          and CDHT or owner of factories or relevant governmental authorities.

     viii. During the 3-year lease term, Company has the option to purchase
          Factory A and the use right of Land A, Factory B and the use right of
          Land B. CDHT shall provide sufficient assistance to Company to handle
          all governmental procedures.

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          (a)  The purchase price for either Factory A or Factory B is
               RMB880/sqm and for either Land A or Land B is RMB80/sqm.

          (b)  The rents paid by Company during the 3-year lease term will be
               deducted from the purchase cost of the land and factory.

          (c)  The use right to Land A and Land B is for a period of not less
               than 50 years.

     ix.  CDHT guarantees that the Company will obtain the right to use each
          piece of Land for a term of at least 50 year should Company decide to
          purchase use right of any of the Land.

     x.   Where the land is at the border of the Hi-Tech Zone, CDHT shall built
          fence at its own expense.

     xi.  The address for Factory A and B shall be Sichuan Chengdu Export
          Processing Zone, #1 New Century West Road, Tianfu Boulevard, Chengdu
          610041, Sichuan Province.

2.   Supply of Power

     CDHT will cause the power supplier to provide the following services in
     relation to the power supply:

     i.   CDHT will cause the relevant power bureau to provide lighting power to
          Company. The Company shall pay for the consumed electricity based on
          the standard electricity charge announced by the power bureau. The
          current rate is as follows:

          (a)  Commercial Rate (current average price of RMB0.57 per kwh):
               Applies to electricity usage for the office lighting;

          (b)  Industrial Rate (current average price of RMB0.47 per kwh):
               Applies to all other usages except those stated above.

     iii. CDHT will provide, at the Company's option, an electricity capacity of
          300 kva with the necessary cables for the startup period of the
          Company for no less than 1 year from the date on which the Company
          starts its business operating in factories. The electricity
          consumption will be charged at the Commercial Rate. The CDHT will, at
          the Company's option, provide an additional 200 kva transformer.
          However, the cost of necessary cables shall be borne by the Company.

     iv.  The Company has the option of building or sourcing a transformer(s)
          from external sources or from CDHT. Should the Company decide to
          source a transformer(s) from CDHT, CDHT shall ensure the completion of
          the construction of such transformer within one month. In all
          instances, CDHT shall connect the transformer within the red-line
          border of the land.

     v.   The cost of electricity, water and gas consumed for the manufacture of
          product for export, is subject to a tax rebate of 13%. Should the tax
          rebate not be reflected in the bills issued to Company, CDHT shall
          coordinate with the relevant service provider and/or relevant
          governmental authority to ensure that the tax rebate is

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          refunded to the Company. Further, CDHT will provide all assistance
          required to obtain the refund from the service provider and/or
          relevant governmental authority.

     vi.  CDHT will provide a power subsidy of 10% based on the actual power
          consumption expenses (gross amount before tax rebate) to the Company
          for the first five (5) years from the date of issuance of the
          Company's business license; the rate of subsidy will be changed to 5%
          for the following five years afterwards. Such subsidy will be payable
          within one (1) month from the payment of the bill to the power bureau.
          In the event the subsidy has not been paid within the one (1) month
          period, the Company shall deduct the outstanding subsidy from the
          lease payment or purchase price of the land and factories. Such
          deduction shall not form part of the calculation for the purchase
          amount of the land and factory, as specified in 1.4.viii.

3.   Dormitories for Managers

(a)  CDHT will lease to the Company dormitory units for the managers of the
     Company at a rate of RMB500/unit/month. Such rate shall remain unchanged
     for a period of three (3) years and any price increase thereafter shall be
     in accordance with or lower than the changing rate of the PRC price index.

(b)  Each unit has two (2) bedrooms, a toilet and a bathroom.

(c)  Power, gas and water fees shall be borne by the Company. The CDHT will
     install power meters to each unit and renovate the bathrooms for the use by
     Company personnel.

(d)  The full cost of all facilities such as bed, chairs and desks shall be
     borne by the Company.

(e)  All residents shall follow the property management regulations.

(f)  CDHT will guarantee the availability of dormitory units to the Company upon
     request by the Company within a one (1) week period if there are units
     available in the dormitory building. In the event that there are no
     available units, CDHT will construct another dormitory building, at no
     expense to PSi, within a six (6) month period and at the originally agreed
     lease rate and terms.

4.   Dormitories for Operators

(a)  CDHT will lease to the Company, dormitory units for the operators of the
     Company at a rate of RMB160/unit/month. Such rate shall remain unchanged
     for a period of three (3) years and any price increase thereafter shall be
     in accordance with or lower than the change rate of the PRC price index.

(b)  Each unit contains one (1) bedroom for 8 persons, and includes access to
     common areas and facilities including toilet, bathroom and public kitchen.

(c)  Power, gas and water fees shall be borne by the Company.

(d)  The full cost of all facilities such as bed, chairs and desks shall be
     borne by the Company.

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(e)  All residents shall follow the property management regulations.

(f)  CDHT will guarantee the availability of dormitory units to Company upon
     request by the Company within a one (1) week period if there are available
     units available in the dormitory building. In the event that there are no
     available units, CDHT will construct another dormitory building, at no
     expense to PSi, within a six (6) month period and at the previously agreed
     lease rate and terms.

5.   Canteen Services

(a)  CDHT will provide non-profit canteen services to the Company.

     The Company has option to use canteen services provided by any third
     parties.

6.   Taxes and Duties

     CDHT represents and warrants to and covenants with PSi the following:

(a)  Enterprise Income Tax - As a foreign investment company incorporating in a
     high-tech zone, the Company is and will be entitled to the applicable
     preferential treatment of 2-year tax exemption followed by 3-year enjoyment
     of the lowest income tax rate (but in no case higher than 10%) starting
     from its first profitable year. Afterwards, the Company will continue to
     enjoy the applicable lowest tax rate (but in no case higher than 10%) if it
     continues to export 70% of its products. If the Company exports less than
     70% of its products, then the tax rate will be 15%.

(b)  The Company is and will be entitled to exemption of the Custom duties and
     VAT for machinery, equipments, construction materials, moulds, and spare
     parts imported hereby. CDHT will assist the Company in the smooth
     importation of second-hand equipments.

(c)  The Company is and will be entitled to exemption of Custom duties and VAT
     for raw materials, spare parts, packing materials, components and units
     imported hereby.

(d)  CDHT will provide bonded warehouse facility for the Company, including
     refund of VAT on items produced locally such as machinery, equipment,
     construction materials, raw materials, packaging materials, moulds and
     spare parts, all of which are made in China.

(e)  Other than those stipulated in the national government regulations, there
     will be no other state, local, city, municipal income taxes, consumption
     taxes, property taxes and fees.

7.   Other Service

(a)  CDHT encourages and supports PSi or its affiliates or the Company to
     establish a semiconductor test and assembly facility in the Hi-tech Zone
     and will provide all assistance, including the establishment of a work
     team, determined by PSi or its affiliates or Company as necessary for
     obtaining preferential policies on import and export, business
     registration, tax and duties, foreign exchange control and environment
     protection.

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(b)  The CDHT shall offer the Company a training subsidy of RMB500,000 on annual
     basis for a term of 5 years. The subsidy will be payable upon the
     establishment of the Company and in the first month of each year
     thereafter. In the event the subsidy has not been paid within the period
     specified herein, the Company shall deduct the outstanding subsidy from the
     lease payment or purchase price of the land and factories. Such deduction
     shall not form part of the calculation for the purchase amount of the land
     and factory, as specified in 1.4.viii.

     The Company is and will be entitled to pay social benefits and social
     securities on a preferential basis according to existing Hi-Tech Zone
     policies, as follows:

--------------------------------------------------------------------------------
                             Current rates applied in   Rates applicable for PSI
                                      Chengdu                    project
--------------------------------------------------------------------------------
Retirement                                20%                       11%
--------------------------------------------------------------------------------
Medical insurance                        7.5%                        4%
--------------------------------------------------------------------------------
Unemployment
Insurance                                  2%                        2%
--------------------------------------------------------------------------------
Accidental Injuries
insurance                             0.6%-2%                        1%
--------------------------------------------------------------------------------
Maternity insurance                      0.6%                      0.6%
--------------------------------------------------------------------------------
Housing reserve                            6%                        6%
--------------------------------------------------------------------------------
Total                                  Ca 37%                     24.6%
--------------------------------------------------------------------------------

     CDHT guarantees that the Company will be able to pay the rate specified
     above. CDHT shall coordinate with the relevant governmental authority and
     shall obtain all the necessary approvals and clearances in the event that
     any other governmental authority/(ies) challenges the legality of this
     rate.

(c)  The basic wages on which social securities will be paid by the Company
     shall not be lower than the lowest wage level of Chengdu, i.e.910
     yuan/month, and shall not be higher than three times of the lowest wage
     level. The aforesaid preferential rates shall not prejudice the level of
     social security applicable to the staff of the Company.

8.   General Provisions

     (a)  Options to Choose Service Providers

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          Notwithstanding the provisions contained herein, PSi or its affiliated
          companies or the Company shall have the right to choose any service
          provider to provide relevant service described in this Agreement
          rather than CDHT.

     (b)  Confidentiality

          Other than for the purpose of performance of this Agreement, CDHT
          shall not disclose to any third party, without the prior written
          consent of PSi, (i) any information on potential investment by PSi or
          any of its Affiliates; (ii) any content of this Agreement and any
          terms and conditions agreed by PSi and CDHT orally or in writing.

     (c)  Non Assignability

          This Agreement and the rights and obligations hereunder shall not be
          assignable by either Party without the prior written consent of the
          other Party, except that a party may assign this Agreement to the
          successor of all or substantially all of its business assets or an
          Affiliated Company without such consent.

          For the purposes of this Agreement, an Affiliated Company shall mean
          any legal entity that either Party may delegate and/or assign all or
          part of the performance of its rights and obligations hereunder,
          wherein at least fifty one (51) percent of the voting shares (or
          similar voting rights), now or hereunder owned or controlled, directly
          or indirectly by PSi or CDHT, as the case may be, or in which PSi or
          CDHT, as the case may be, otherwise has the ability to direct the
          management, but such legal entity shall be considered to be an
          Affiliated Company only for so long as such control exists.

     (d)  PSi's Investment

          CDHT acknowledges and agrees that there are several factors that will
          affect PSi or its affiliated companies' decision to make an investment
          in the Hi-Tech Zone, or the final amount of that investment, whether
          in the Phase No. 1 or in subsequent phases. Based upon the above
          understanding, should PSi or its affiliated companies decide not to
          invest in Hi-Tech Zone or alter its investment amount after the
          execution and delivery of this Agreement, PSi or its affiliated
          companies shall not bear any liability to CDHT notwithstanding any
          provision in this agreement. In the event PSi cancels the investment
          project, then the CDHT will not be liable to the obligations as
          committed in this agreement.

     (e)  Most Favorable Treatment

          CDHT undertakes to make its best efforts to help the Company to obtain
          the most favorable treatment in PRC as a wholly owned foreign
          enterprise in Hi-Tech Zone during the term of this Agreement, while
          realizing that relevant PRC laws and regulations may be amended from
          time to time.

     (f)  Entire Agreement

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          This Agreement shall constitute the entire agreement between the
          parties hereto with regard to the subject matter hereof and supersede
          all previous discussions, negotiations and agreements between the
          Parties regarding the subject matter hereof.

     (g)  Effectiveness

          The obligations of PSi under this Agreement shall become effective
          upon the issuance by the relevant Governmental Authority/ies of the
          Company's business license, customs permits, and such other approvals
          and permits as may be necessary to establish and operate an Assembly
          and Test Facility Factory in the Sichuan Chengdu Export Processing
          Zone, Chengdu, Sichuan Province. The obligations of all other parties
          to this contract shall become effective from the execution date and
          continuously effective during the operational period of the Company.

     (h)  Validity of the Agreement

          If any provisions contained herein become illegal under PRC laws
          during the term of this Agreement, the parties shall, through friendly
          negotiations, reach supplemental agreements in accordance to Section
          8(f) of this Agreement. The invalidity, nullity and unenforceability
          of any provision hereof shall not influence or prejudice the validity,
          effectiveness and enforceability of other provisions hereof.

     (i)  Termination

          PSi has right to terminate this Agreement upon giving a one-month
          prior written notice to CDHT.

     (j)  Language and Copies

          This Agreement shall be written in both English and Chinese. This
          Agreement will be signed in 4 (four) originals, with each party
          holding two (2). All the signed originals shall bear equal legal
          effects.

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     This Agreement is signed by the duly authorized representatives of each of
     the parties hereto on the date first written above.

PSi TECHNOLOGIES, INC.                  CHENGDU HI-TECH ZONE

By:                                     By:


/s/ Arthur J. Young, Jr.                /s/ Jing Gang
-------------------------------------   ----------------------------------------
Name: Arthur J. Young, Jr.              Name: Jing Gang
Title: Chairman and CEO                 Title: Director of the Management
                                        Committee of Chengdu Hi-Tech Zone and
                                        Assistant to the Mayor of the People's
                                        Government of Chengdu

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                                     Annex A

                          Site Map of Factory and Land

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