SUNNYVALE, Calif., May 15, 2006 - UMC (NYSE: UMC; TSE: 2303), a leading global semiconductor foundry, today announced that Raymond Leung has joined the company as vice president of Memory IP Development. The creation of this new position will strengthen UMC's internal embedded memory development capabilities at very deep submicron process technologies. Mr. Leung will report directly to Patrick T. Lin, chief SoC architect, system and architecture support at UMC.

Patrick commented, "Due to the large demand UMC is experiencing for its foundry services, we are strengthening our internal design resources as well as continuing to work closely with our IP partners in order to enhance our overall design support. The addition of Raymond's expertise to UMC's embedded memory development will help turn this area into a strong competitive advantage for our customers designing next generation SoCs on UMC's advanced processes."

Raymond brings over 20 years of semiconductor industry experience to UMC. Prior to joining the foundry, Mr. Leung was the executive vice president at Celestial Semiconductor. He also served as vice president of engineering at Virage Logic, where he was responsible for developing the foundry libraries and managing most of the remote development operations. Other companies benefiting from his expertise include LSI Logic Corp where he served as senior director, and prior to that Philips Semiconductor where he was a senior design engineer in the PLD division. Raymond earned his BSEE degree at Columbia University in 1981, and his MSEE degree at Stanford University in 1982.

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 volume production 90nm, industry-leading 65nm, and mixed signal/RFCMOS. UMC's 10 wafer manufacturing facilities include two advanced 300mm fabs; Fab 12A in Taiwan and Singapore-based Fab 12i are both in volume production for a variety of customer products. The company employs approximately 12,000 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.