光阻回刻工艺缺陷与改善方法研究  

Study and Improvement on the Defects of PREB Process

作　　者：阚琎 苏良得 KAN Jin;SU Liangde(Shanghai Huali Integrated Circuit Manufacturing Co.,Ltd.,Shanghai 201314,China)

机构地区：[1]上海华力集成电路制造有限公司,上海201314

出　　处：《集成电路应用》2024年第5期62-65,共4页Application of IC

摘　　要：阐述在金属栅极(例如AL)半导体芯片制造工艺中通常需要引入一段特有流程用来去除多晶硅(Poly)并进行金属再填充。光阻回刻工艺作为该流程中的关键步骤,主要目的是去除Poly顶端的硬质掩膜,便于后道工艺对Poly进行刻蚀。因为NMOS和PMOS的硬质掩膜存在高度差异,以及光阻在不同图形密度区域厚度不同,导致工艺窗口紧张,实际生产维护困难,容易出现包括多晶硅残留在内的多种缺陷,严重影响产品最终良率。为此,通过对缺陷进行分类,探究形成机理,提出对应在线监控方式,能够降低缺陷发生率,并尝试对工艺条件进行优化,提升整体工艺窗口。This paper describes that in metal gate(e.g.AL)semiconductor chip manufacture,it is necessary to add a special process to remove Poly and metal refill.PREB(Photo Resistor Etch Back)is a key step in the process,the main purpose isto remove the poly hardmask before etching poly.Due to the height difference between the hard mask of NMOS and PMOS,and the different thickness of the photoresistance in different graphic density areas,the process window is tight,and the production maintenance is difficult.It is easy to suffer a variety of defects including Poly Residue,which seriously affect the final yield of the product.This paper classifies the defects,explores their formation mechanism,and puts forward monitoring methods to reduce the incidence of defects.At the same time,try to optimize the process conditions and improve the overall process window.

关 键 词：集成电路制造 金属栅极 光阻回刻工艺 缺陷分析 工艺窗口改善 

分 类 号：TN405[电子电信—微电子学与固体电子学]