彩虹缺陷的失效验证方法及机理分析

Study on the verification method and failure mechanism for rainbow defects

随着集成电路特征尺寸的不断缩小,对晶圆制造工艺提出来更大挑战。彩虹效应是指晶圆局部或边缘处因异物,膜内分层,镀层厚度等原因导致晶粒表面所呈现的变色现象。本文基于模拟开关芯片开展失效分析,在芯片内晶粒局部检测到彩虹效应。并通过应用失效验证,电学参数测试,依据EMMI,OBIRCH的漏电流定位结果及电路原理图分析验证了彩虹效应对集成电路的电性能参数的影响。同时,借用FIB,EDS,XPS等物理分析方法,揭示了彩虹效应的失效机理。该案例展示了EMMI,OBIRCH在集成电路内部缺陷无损定位和分析的作用,为边缘缺陷的验证提供技术手段。

With the continuous reduction in the feature size of integrated circuits,greater challenges are presented to the wafer manufacturing process.Rainbow effect refers to the discoloration on the surface of the crystal due to foreign matter,delamination in the film,thickness of the coating,etc.In this paper,based on the failure analysis of analog switch chip,rainbow effect is detected in the local grains of the chip.Through the application failure verification,electrical parameter test,EMMI,OBIRCH leakage current positioning results and circuit schematic analysis,the influence of the rainbow effect on the electrical performance parameters of the integrated circuit is verified.Simultaneously,by using FIB,EDS,XPS and other physical analysis methods,the failure mechanism of rainbow effect is revealed.This case demonstrates the role of EMMI and OBIRCH in the nondestructive location and in analysis of internal defects in integrated circuits,meanwhile and provideses the technical means for the verification of edge defects.