具有交替型相移掩模技术的CAD系统

随着超大规模集成电路制造进入深亚微米时代,版图上相邻特征区域的光刻质量受光学临近效应的影响越来越大.交替型相移掩模技术通过将相邻区域的相位进行180°反转,使干涉效应互相抵消,从而被认为是提高光刻分辨率最实用的技术之一.我们以当今的最新研究成果为基础,开发了一个用于暗域交替型相移掩模设计技术的CAD原型系统.为应对随版图尺寸呈指数增加的相位冲突,还提出了一个自适应粒度的划分方法,以减少计算时间.该算法和原型系统的有效性在多个不同尺寸的实际版图上得到了成功的验证.

CAD System Adopting Alternating Phase-Shift Mask Technology

As the VLSI fabrication enters into deep sub-micron era, the adjacent layout features with small intervals will be quite effected by the Optical Proximity Effect(OPE). Alternating Phase-Shift Mask (AltPSM) technology, which shifts light phase with 180 degrees difference between adjacent aperture pairs, is considered to be one of the most practical techniques for enhancing the resolution of lithography.An efficient CAD prototype for dark field AltPSM based on the recently proposed techniques is developed. To cope with the exponential phase-conflict growth with layout size, a partition method to reduce the amount of computing time is proposed.The validity of algorithm with the prototype is demonstrated using several industry layouts.