报告人：       华佑男博士    Dr. Hua Younan

新加坡特许半导体制造公司 质量和可靠性保证－失效分析部经理Manager of Quality & Reliability Assurance-Failure Analysis Department，Chartered Semiconductor Mfg Ltd，60 Woodlands Industrial Park D Street 2, Singapore 738406  Tel: 65-91863281 Fax: 65-63622935       E-Mail: huayounan@charteredsemi.com

题目:    半导体和晶片制造中的氟污染和腐蚀的失效分析Failure analysis of Fluorine contamination and corrosion in semiconductor and wafer fabrication

摘要:   华佑南博士从事半导体、集成电路和晶片制造的失效分析和质量控制二十余年，已发表150篇论文，获5项失效分析专利。报告以半导体氟污染和腐蚀的控制为例，采用X射线荧光分析、扫描电子显微镜及能谱（EDS）和Auger、XPS、TOF-SIMS等先进分析手段，研究半导体器件缺陷产生的物理化学机制和解决方法。

时间:   2005年9月5日（星期一 ）下午3 : 00

地点:   清华大学东门信息学院大楼1－101

 清华大学信息科学技术学院

联系人：查良镇

联系电话：62782735

（学术报告英文摘要及报告人简历附后）         
Abstract:

Fluorine contamination on microchip Al bondpads will result in corrosion, affect quality of Al bondpads and pose problem such as non-stick on pad (NSOP) during wire bonding at assembly process. In this technical talk, a fluorine contamination case in wafer fabrication will be studied. SEM, EDX, TEM, AES and IC techniques were employed to identify the root cause of the failure. XPS/ESCA and TOF-SIMS advanced tools were used to study the chemical and physical failure mechanism of fluorine-induced defects. An un-known Al compound was found using XPS technique and identified it as [AlF6]3- using electrochemical theories and TOF-SIMS technique. A theoretical electrochemical model to reveal the secrets of Fluorine-Induced Corrosion on Al bondpads is proposed. Based on the model, F-induced corrosion is defined into two corrosion steps: F corrosion and [OH] corrosion. To support this new theoretical model, the author has provided substantiating data from TOF-SIMS analysis and other failure analysis techniques. According to the theoretical model of Fluorine-induced Corrosion proposed, fluorine contamination on Al bondpads will cause two types of corrosions. First, fluorine reacts with Al and forms a complex compound [AlF6]3- on the affected area, which we will refer to as Fluorine Corrosion. Once the compound of [AlF6]3- forms on Al bondpads, it will form an Anode and cause further electrochemical reactions from O2, N2 and H2O (moisture) at the Cathode. The new products of further electrochemical reactions will be [OH]- and [NH4]+ ions. The new product of [OH]- ions will react with Al and cause further Al corrosion on bondpads and form corrosive product consisting of Al(OH)3, which we will refer to as [OH]- Corrosion. The new product of [NH4]+ ions will combine with [AlF6]3- and form a corrosive complex compound (NH4)3(AlF6), which was detected by TOF-SIMS. Finally the control & monitoring method of fluorine contamination level in wafer fabrication will be also discussed.

About the Speaker

Dr. Hua Younan received his M, S. Degree in Analytical Chemistry from Nanjing University in 1988 and Ph. D degree in Physics from National University of Singapore in 1994. Dr Hua joined Chartered Semiconductor Manufacturing Ltd, Singapore Technologies in 1995. He is presently a Manager of Quality & Reliability Assurance-Failure Analysis Department. Dr. Hua has more than 20 years of working experience in analytical chemistry and failure analysis of semiconductor, integration circuit and wafer fabrication. Since 1982, he has published more than 150 technical papers and filed 5 patents on failure analysis of semiconductor & wafer fabrication. Dr Hua has conducted deeply theoretical studies in certain areas such as failure analysis techniques in wafer fabrication, microchip Al bondpad corrosions & eliminating solutions, chemical deprocessing techniques & elimination of silicon crystalline defects, X-ray fluorescence analysis & energy?dispersive X-ray microanalysis, and surface analytical techniques (Auger, XPS, TOF-SIMS).