Prevention of Increased CoSi2 Sheet Resistance by Storage of Silicon Wafers in a Closed Pod

摘要

A minienvironment consisting of nitrogen-purgedwafer transfer unit and a hermetically sealed aluminum pod wasdeveloped and used for wafer transport from the wafer-cleaningequipment to the cobalt-deposition equipment prior to the cobaltdeposition step in the cobalt-silicide formation process. As aresult of employing the closed pod system, an increase in sheetresistance of cobalt silicide was prevented without increasing thejunction leakage current caused by prevention of the growth ofnative oxides on the silicon surfaces.