Patent ID: 9422187
Filing Date: 2016-08-23
CPC Classification: B23K,C03B,C03C

Claim Text:
1. A high purity sintered silica glass sheet comprising: a first major surface; a second major surface opposite the first major surface; an edge section surrounding the first and second major surfaces and defining an outer perimeter of the silica glass sheet; at least 99.9 mole % silica, wherein a sodium (Na) content of the silica glass sheet is less than 50 ppm; and an average thickness between the first major surface and the second major surface of less than 500 μm; wherein the edge section has a maximum thickness around the other perimeter that is greater than the average thickness, wherein the maximum thickness of the edge section is located less than 300 μm from the outer perimeter; wherein a roughness (Ra) of the first major surface is between 0.025 nm and 1 nm over at least one 0.023 mm