基于热激光激发OBIRCH技术的失效分析

Failure Analysis of the Optical Beam Induced Resistance Change Based on Thermal Laser Stimulation Techniques

针对传统失效定位技术如光辐射显微镜(EMMI)和红外成像等无法对互连失效进行定位的问题,在半导体失效分析中引入了热激光激发(TLS)技术进行失效定位。该技术应用激光束对材料进行加热,改变材料电阻特性,从而检测到缺陷。光束感生电阻变化(OBIRCH)技术即为TLS技术的一种。对技术原理进行了综述,并利用OBIRCH激光扫描显微镜对功率金属氧化物半导体场效应晶体管(MOSFET)、集成电路静电放电(ESD)保护端口和金属-绝缘体-金属(MIM)电容进行失效定位。结果表明TLS技术对于短路、漏电以及电流路径成像的定位十分有效。特别是难以观察的微小失效如晶体管击穿、铝硅互熔短路和介质层裂纹等。OBIRCH技术对精确和快速地定位多层金属化布线、新型封装的短路和阻性缺陷等方面有着重要的作用。

Traditional fault localization techniques such as the photon emission microscopy （EMMI） and infrared microscopy were difficult in interconnecting failure analysis, thus the thermal laser stimulation （TLS） technique was introduced to solve the problem in the semiconductor failure analysis. The material was heated by the laser beam, of which the resistance characteristic was changed, and the defects were detected. The optical beam induced resistance change （OBIRCH） is one of the thermal laser stimulation techniques. The basic principle of the OBIRCH technique was summarized. The failure analysis of the power MOSFET, integrated circuit electrostatic discharge （ESD） and metal-insulator-metal （MIM） capacitor were performed by using OBIRCH laser scanning microscopy. The results show that the TLS technique was capable and efficient in fault localization of short circuit, current leakage and current path imaging, especially for micro defects such as the transistor breakdown, aluminum silicon melt and MIM capacitor failure. OBIRCH technique has played an important role in precise and fast fault localization for short circuit and resistive defects in multilayer interconnection and novel package.