High Pressure Phase Transformation Machining of Silicon

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Abstract

Supporting Materials

Abstract

Single point diamond turning was performed on (100) Si along the <011> direction using both -30° and -45° diamond tools with feedrates of 1 and 5 µm/rev. Machining was performed using a t-lathe and a parallel fly cutting setup. All samples were analyzed with Raman spectroscopy, and cross sectional Transmission Electron Microscopy (TEM). Dislocation loops and slip planes were found at depths up to 250 nm below the surface of both feedrates of the t-lathe machined samples. In the fly cut samples no dislocations were found, and the a-Si Fly cut samples were machined with two separate set of tools, and using Raman spectroscopy it was found that depending on tool edge design an amorphous layer was not always created. This was contradicting by the TEM images showing a thin a-Si layer. A correlation between the Raman spectra and cross sectional TEM images of the diamond turned silicon was not able to be determined. TEM analysis is still needed to analyze subsurface damage, and to determine the deformation mode (i.e. high pressure phase transformation (HPPT) or dislocation movement). Recent results have provided more insight into the lack of dependence between feed rate and the depth of the amorphous layer.

Supporting Materials

• High Pressure Phase Transformation and Ductility in Diamond Turned Single Crystal Silicon

The following faculty, students, and PEC affiliates are involved in this project: