UMC Holds Grand Opening Ceremony for its New R&D Headquarters

Company's 27^th anniversery marks opening of R&D center located at UMC's 300mm fab complex in Tainan Science Park

HSINCHU, Taiwan, May 22, 2007 - UMC (NYSE: UMC, TSE: 2303), a leading global semiconductor foundry, today held the grand-opening ceremony for its new R&D center for nanometer technologies to coincide with the company's 27^th anniversary. The facility, which will focus on R&D for advanced nanometer technologies for 300mm manufacturing, is located adjacent to 300mm Fab 12A at UMC's Tainan Science Park site. The close proximity of the new R&D center to UMC's most advanced fabs enhances the company's ability to rapidly move newly-developed technologies to mass production, resulting in increased competitiveness for UMC customers. The R&D center will be staffed with over 1,000 employees when fully operational, most of which will consist of R&D engineers.

Dr. Jackson Hu, chairman and CEO of UMC, said, "On the anniversary of our 27^th year, we are happy to celebrate the opening of our new R&D center that will enable us to further strengthen our position as a global leader in advanced-foundry technologies. This R&D facility, the first of its kind in Southern Taiwan, will help stimulate the local economy as it will create many job opportunities in Southern Taiwan. The grand opening, along with the ongoing construction of UMC's second phase of 300mm construction on the same site, underscores UMC's strong commitment to continuing its future growth and investment in Taiwan."

The R&D center occupies a nearly 6,000 square meter area of UMC's 155,660 square meter Tainan site. The ten-story building features independent cleanroom R&D areas for the continued development of 45nm and below advanced process technologies, as well as restaurants and a fully equipped recreation center for employees.

Today's grand opening and anniversary event was attended by local and international media, government officials, and UMC executives, customers, and suppliers.

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 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 which are both in volume production for a variety of customer products. The company employs approximately 13,000 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.

Contacts: