Reassessment of defect models in graphite strip heater zone-melt recrystallized material by non-destructive thin film diagnostics

Abstract

Summary form only given. Recent state-of-the-art graphite strip heater ZMR wafers were examined by nondestructive diagnostic tools especially suited for the characterization of very thin Si films. In particular, glancing angle reflection X-ray topography, which revealed slip dislocation networks in the recrystallized superficial Si film, was used. It was found that the dense orthogonal network of dislocations is aligned along and superimposed on the subboundaries. According to TEM analysis the dislocation density ranges between 10/sup 7//cm/sup 2/ to 10/sup 8//cm/sup 2/ maximum. This orthogonal dislocation network has never been observed before by preferential chemical defect etching because the 0.5 mu m ZMR Si films are too thin to develop detectable each pits. As a further evaluation, transmission electron microscopy (TEM) was applied to selective areas of ZMR wafers. TEM analysis of these films showed orthogonal rows of dislocation clusters aligned along the directions. >