Accuracy of differential method to distinguish crystal originated particles from light point defects in Czochralski-grown silicon wafers

To distinguish crystal-originated particles (COPs) from light point defects (LPDs) in Czochralski-grown silicon (Si) wafers, we developed a differenti al method and studied its performance. To distinguish COPs from LPDs, we co mpared the difference in LPD properties before and after SC-1 cleaning. COP is defined as an LPD whose location does not change and becomes large in s ize after SC-1 cleaning. COPs obtained by the differential method were dire ctly observed by atomic force microscopy (AFM) and the accuracy of counting COPs was estimated. Under optimum conditions, COP detection exceeded 75%, making the differential method useful for the estimation of COPs in CZ-Si w afers. (C) 2000 Elsevier Science B.V. All rights reserved.