UMC Increases its Stake in UMCi

Taipei, Taiwan, R.O.C. – March 31, 2004, - United Microelectronics Corporation (TAIEX: 2303, NYSE: UMC), announced that it would purchase 90 million UMCi shares from EDB Investments Pte. Ltd. (EDBI), the wholly owned investment arm of Singapore’s Economic Development Board (EDB). The total cost of the purchase is SGD 201,402,000. After this transaction, UMC will own 84.96% of UMCi, an increase from the current level of 75.05%.

As the semiconductor industry recovery gains momentum, UMC will continue to enhance its support of UMCi, maintaining UMCi's status as the most advanced semiconductor foundry in Singapore. UMCi is currently in full-scale production, and is focused on manufacturing products based on UMC's 0.13um and below technologies. UMCi has been extremely successful in leveraging its parent company's extensive 300mm experience. This knowledge and experience is currently being applied to its rapid production ramp-up, along with the implementation of single wafer processing to reduce lot size and cycle time. Production volume for the state of the art automated facility is expected to reach 10,000 wafers by the end of 2004.

UMCi is located on a 12-hectare (30 acres) site in Singapore's Pasir Ris Wafer Park. Singapore is a rapidly emerging global IC manufacturing hub, and its well-established infrastructure and friendly government policies have attracted investment from the world's leading semiconductor companies.

About UMC
UMC (NYSE: UMC, TSE: 2303) is a leading global semiconductor foundry that manufactures advanced process ICs for applications spanning every major sector of the semiconductor industry. UMC delivers cutting-edge foundry technologies that enable sophisticated system-on-chip (SOC) designs, including 90nm copper, 0.13um copper, embedded DRAM, and mixed signal/RFCMOS. UMC is also a leader in 300mm manufacturing; Fab 12A in Taiwan is currently in volume production for a variety of customer products, while Singapore-based UMCi has just entered volume production. UMC employs over 8,500 people worldwide and has offices in Taiwan, Japan, Singapore, Europe, and the United States. UMC can be found on the web at http://www.umc.com.

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