Ma Xu, Arce Gonzalo R
Department of Electrical and Computer Engineering, University of Delaware, Newark, DE 19716, USA.
Opt Express. 2009 Mar 30;17(7):5783-93. doi: 10.1364/oe.17.005783.
Optical proximity correction (OPC) and phase-shifting mask (PSM) are resolution enhancement techniques (RET) used extensively in the semiconductor industry to improve the resolution and pattern fidelity of optical lithography. Traditional RETs, however, fix the source thus limiting the degrees of freedom during the optimization of the mask patterns. To overcome this restriction, a set of simultaneous source and mask optimization (SMO) methods have been developed recently where the resulting source and mask patterns fall well outside the realm of known design forms. This paper focuses on developing computationally efficient, pixel-based, simultaneous source mask optimization methods for both OPC and PSM designs, where the synergy is exploited in the joint optimization of source and mask patterns. The Fourier series expansion model is applied to approximate the partially coherent system as a sum of coherent systems. Cost sensitivity is used to drive the output pattern error in the descent direction. In order to influence the solution patterns to have more desirable manufacturability properties, topological constraints are added to the optimization framework. Several illustrative simulations are presented to demonstrate the effectiveness of the proposed algorithms.
光学邻近校正（OPC）和相移掩膜（PSM）是分辨率增强技术（RET），在半导体行业中被广泛使用，以提高光学光刻的分辨率和图案保真度。然而，传统的分辨率增强技术固定了光源，因此在掩膜图案优化过程中限制了自由度。为了克服这一限制，最近开发了一组同时进行光源和掩膜优化（SMO）的方法，其中生成的光源和掩膜图案远远超出了已知设计形式的范围。本文着重为OPC和PSM设计开发计算效率高、基于像素的同时进行光源和掩膜优化方法，在光源和掩膜图案的联合优化中利用协同作用。傅里叶级数展开模型用于将部分相干系统近似为相干系统的总和。成本敏感度用于在下降方向上驱动输出图案误差。为了使求解图案具有更理想的可制造性，在优化框架中添加了拓扑约束。给出了几个说明性模拟，以证明所提算法的有效性。
