Determination of ultra-trace impurities in semiconductor-grade chemicals by inductively coupled plasma mass spectrometry following a concentration pretreatment technique

• Main Authors: I-HSING LIN, 林益興
• Other Authors: W.H. Ding
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/35230127812038052158

碩士 === 國立中央大學 === 化學研究所 === 90 === The metallic impurity level of process chemical for integrated circuits industry is getting lower, particularly as the industry moves to larger wafer size and smaller line-widths. To avoid contamination of the wafer surface by the cleaning solution itself, the purity of the reagents must be extremely high. The accurate determination and control of metallic impurities is key to maintaining high production yield. Traditionally, inductively coupled plasma mass spectrometry (ICP-MS) has been the technique of choice for ultra-trace element determinations in high-purity chemicals. However, direct determination by ICP-MS is unsatisfactory owing to insufficient detection power and interference from matrix of the chemicals. In order to achieve the high sensitive ICP-MS determination, impurity were concentrated by a stabilization evaporator and measured under normal and cool plasma conditions. This study describes the determination of metallic impurities in hydrogen peroxide by ICP-MS after volatilization pretreatment. The result of quantitative spike recoveries at 5 ppt level are 80~113%, indicated excellent measurement accuracy, attain SEMI Grade 5 purity levels.