使用测试图形法优化亚分辨率辅助图形

Optimizing Sub-resolution Assist Features Using Test Pattern Method

在亚波长光刻领域,基于规则插入亚分辨率辅助图形是一种重要的技术。现有的方法需要利用经验改善亚分辨率辅助图形,且不考虑光学邻近校正的效果。提出了一种新的利用测试图形优化亚分辨率辅助图形的方法。与一般的光学邻近校正流程结合,该方法能解决工艺窗口过小和亚分辨率辅助图形刻出等问题。通过对标准电路版图的测试,对边放置误差和工艺窗口进行了测量。边放置误差相比传统方法减小了10%,同时,不同工艺窗条件下的边放置误差也有改善。

In the field of sub-wavelength lithography, the rule-based sub-resolution assist features insertion is an important technology. Regardless of optical proximity correction effect, the conventional method needs experience to better SRAF. A new optimizing SRAF method using test patterns is presented. Combined with conventional optical proximity correction flow, it can solve problems such as small process window and SRAF print-out. Edge placement error （EPE） and process window are measured and tested on the standard benchmark circuits. The EPE has decreased 10%, while all EPEs under different process windows have also bettered.