United Microelectronics Corp.

Chen-Hao Hwang

Lien-Sheng Chung

Wei-Jyh Liu

A phase-shifting mask structure has a base plate, a pattern zone on the base plate and a peripheral region on the periphery of the base plate around the pattern zone. The peripheral region and the pattern zone further have a plurality of alignment-checking patterns and alignment slits. Each alignment-checking pattern has a first pattern of light-blocking thin films and a second pattern of light-penetrating thin films. Similarly, each alignment slit has a third pattern of light-blocking thin films and a fourth pattern of light-penetrating thin films. In this invention, absolute light-blocking thin films are used in the light-blocking portions of the alignment-checking pattern and the alignment slits instead of the semi-transparent thin films in a conventional system. Thus, alignment checking errors due to the distortion of fiducial marks are minimized, and mask layers are more precisely aligned.

Growing community of inventors

Chang-Hua Hsien, Taiwan

Chen-Hao Hwang