Defect observation on a 12-in. silicon wafer using large sample atomic force microscopy

As semiconductor devices have become more highly integrated and miniaturize d, defects originating within single-crystal silicon occur more frequently. Defect observation of silicon wafer surfaces using atomic force microscopy (AFM) is an analysis technique that reduces defect density on silicon surf aces and, thereby, increases yield (Ref. 1). We have developed an AFM that can directly observe the entire surface of next-trend, 12-in. wafers. We ob served the defects of 12-in. Czochralski (CZ) wafers and compared the resul ts with those of 8-in. wafers. We also observed the defects of 12-in. epita xial Si wafers as a reference. The defects of the 12- and 8-in. CZ wafers a re similar, and the 12-in. wafers display two types of defects in the silic on crystals: (1) Crystal originated particle, which is a shape surrounded b y a {111} facet, and (2) dislocation loops. These defects are caused when c rystals are lifted, and reflect the lifting conditions (Ref. 2). Although, there were fewer defects on the epitaxial Si wafers than on the CZ wafers, defects like hillock were found on the epitaxial Si wafers. (C) 2000 Americ an Vacuum Society. [S0734-211X(00)01603-6].