Transmission electron microscopy of nanomachined silicon crystals

作者：Keith E. Puttick, Lawrence Whitmore, Choung Lii Chao, Anthony E. Gee · 发表于：Philosophical magazine. A/Philosophical magazine. A. Physics of condensed matter. Structure, defects and mechanical properties · 年份：1994 · DOI：10.1080/01418619408242212 · 被引用次数：70 · 研究领域：Advanced Surface Polishing Techniques、Force Microscopy Techniques and Applications、Diamond and Carbon-based Materials Research

Silicon substrate slices in (111) or (001) surface orientation have been machined in two ways: precision ground by a diamond abrasive wheel to a surface roughness R a ≈ 11 nm, or turned on a highly stiff single-point diamond turning machine to R a,≈0·5 nm. Transmission electron microscopy of cross-sections of the machined surfaces has established the following. The mean depth of permanent damage in both cases lies in the range 100–400 nm. In the ground specimens the damage depth is very variable, and the damage consists of regions of well defined dislocation loops on several slip systems, other regions with a very high density of irregular dislocation arrays, and occasional microcracks up to 500nm deep which do not always intersect the surfaces. Patches of amorphous silicon are also observed. Beneath the turned surfaces the damage appears more homogeneous, consisting of dislocation loops predominantly on a single slip system in any given region of the specimen.