Electronic and Semiconductor Properties

The hardness of single-crystal diamond varies as a function of the crystal orientation by aimost a factor of two. This is also true of CVD diamond, and the hardness vaiues depend on which crystal face is in contact with the indenter of the testing device. 

Wear resistance of CVD diamond is generally superior to that of the single-crystal material since the wear of diamond occurs by chipping. Since CVD diamond is a poiycrystalline material, chipping stops at the grain boundary whiie, in a single-crystal, the entire crystal is sheared off. 

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