United Microelectronics Corp.

Chien-Ming Wang

Jiunn-Ren Hwang

I-Hsiung Huang

Kuei-Chun Hung

Chang-Jyh Hsieh

Chien-Wen Lai

Feng-Yuan Chang

A method of correcting an optical mask pattern. A third pattern having a first strip-like pattern and a second strip-like pattern is provided. The first strip-like pattern attaches to the mid-section of the second strip-like pattern. A first modification step is conducted. A pair of assistant patterns is added to the respective sides of the first strip-like pattern to form a first modified pattern. A second modification step is conducted to shrink a portion of the first strip-like pattern to form a second modified pattern. Dimension in the reduced portion of the first strip-like pattern is a critical dimension of a main pattern. A third modification step is conducted using an optical proximity correction method. The second modified pattern is modified to a third modified pattern.

Optical mask correction method

The present invention provides An alternating phase shifting mask (Alt-PSM), that is to be used in a double exposure lithographic process with a light source of 248 nm. The Alt-PSM comprises: (1) a quartz substrate; (2) at least one semi-dense line on the substrate, wherein the semi-dense line is adjacent to a clear region with a width larger than 2 nm on one side and on the other side is adjacent to a dense-line pattern with a narrow pitch; (3) a first phase shifting region, which is located between the dense line pattern and the semi-dense line pattern and is adjacent to the semi-dense line; and (4) a second phase shifting region with a predetermined width, which is adjacent to the semi-dense line and located on the side opposite to the first phase shifting region; wherein the phase difference between the first phase shifting region and the second phase shifting region is 180 degree.

Alternating phase shifting mask

Growing community of inventors

Hsinchu Hsien, Taiwan

Chien-Ming Wang