电子束光刻HSQ显影对比度中的图形密度效应  

Pattern Density Effect in Development Contrast of Electron Beam Lithography HSQ

作　　者：梁惠康 段辉高 Liang Huikang;Duan Huigao(College of Mechanical and Vehicle Engineering,Hunan University,Changsha 410082,China;Guangdong-Hong Kong-Macao Greater Bay Area Institute for Innovation,Hunan University,Guangzhou 511300,China)

机构地区：[1]湖南大学机械与运载工程学院,长沙410082 [2]湖南大学粤港澳大湾区创新研究院,广州511300

出　　处：《微纳电子技术》2024年第2期137-144,共8页Micronanoelectronic Technology

基　　金：国家自然科学基金优秀青年科学基金项目(51722503)。

摘　　要：氢倍半氧硅烷(HSQ)是一种高分辨的电子束抗蚀剂,其稀疏结构的分辨率已证实达到亚5 nm。但在实际应用中,很难达到约10 nm周期的密集结构,其中间隙残胶问题是无法实现更高分辨率的根本原因。利用传统大块薄膜获取的显影对比度进行理论计算,得到的结果与实际曝光的分辨率极限存在较大差异。针对这一问题,提出了与图形相关的显影对比度,提高了传统显影对比度在密集图形分辨率极限预测中的适用性。对HSQ的微观显影机理进行了阐述,分析了大块薄膜、亚10 nm周期密集高分辨结构显影过程和显影对比度曲线差异,预测和实验验证了超稀疏结构的超高显影对比度(线剂量对比度约为114)。该研究为改善HSQ工艺及提升计算光刻模型的精度提供了新的思路。Hydrogen silsesquioxane(HSQ)is a high-resolution electron beam resist,whose resolution of sparse structures has been confirmed to reach sub-5 nm.However,in practical applications,it is difficult to obtain dense HSQ structures of about 10 nm pitch,and the resist residue in the gaps is a key reason of the inability to achieve higher resolution.The development contrast obtained by traditional bulk films was used to calculate the theoretical resolution limit of HSQ.The result shows large differences with the resolution limit of actual exposure.To solve the problem,a pattern-related development contrast was proposed,and the applicability of traditional development contrast in prediction of resolution limit for dense structures was improved.The microcosmic development mechanism of HSQ was described,and the development process and development contrast curve differences of bulk thin films and sub-10 nm periodic dense high-resolution structures were analyzed.In addition,the ultra-high development contrast of ultra-sparse structures(the development contrast of line dose is about 114)was predicted and verified.The study provides a new idea for improving the HSQ process and promoting the accuracy of computational lithography model.

关 键 词：电子束光刻(EBL) 氢倍半氧硅烷(HSQ) 显影对比度 分辨率极限 显影机理 图形密度效应 

分 类 号：TN305.7[电子电信—物理电子学]