Papers by Keyword: Single Wafer Cleaning System

Abstract: High-performance drying techniques using IPA (isopropyl alcohol) are widely used in the silicon wafer cleaning process. IPA-based drying techniques help prevent the formation of watermarks because they effectively displace any water remaining on a wafer surface. They are thus frequently used in the single wafer cleaning system for advanced devices in which ultra-clean process performance is required. However, as devices are becoming physically smaller, the formation of extremely small defects during cleaning has become a serious problem. It is therefore important to elucidate the mechanism of the defect formation and to take measures to prevent it for future device technologies in which small-size defects can be killer defects during production. In this paper, we performed experiments focused on the process chamber atmosphere in IPA drying of the single wafer cleaning system and describe the mechanism of the defect formation.

Abstract: While batch wafer cleaning processes have been conventionally used in the semiconductor manufacturing for many years, the use of single wafer cleaning processes in the manufacturing has recently become increasingly widespread. Single wafer cleaning processes have the advantages of reducing particle and metal contamination, however, electric charge or electrostatic discharge phenomena occurring in these processes causes serious problems such as device destruction through insulation failure and circuit disconnection [1,2]. Well-known examples are the breakdown of the ultra-thin gate oxide and the dissolution of Cu wiring due to charging-up damage in de-ionized water rinsing, which occur during the single wafer wet cleaning process in semiconductor manufacturing. We investigated the problem of wafer defects caused by electrostatic discharge and characterized them using transmission electron microscope (TEM) and energy dispersive X-ray (EDX) analyses.