Sapphire substrates

摘要

A sapphire substrate includes a generally planar surface having a crystallographic orientation selected from the group consisting of a-plane, r-plane, m-plane, and c-plane orientations, and having a nTTV of not greater than about 0.037 µm/cm 2 , wherein nTTV is total thickness variation normalized for surface area of the generally planar surface, the substrate having a diameter not less than about 9.0 cm.