Patent ID: 8012314
Filing Date: 2011-09-06
Classification: C23C,G03F

Abstract:
1. The manufacturing method of a photo mask blank having at least a thin film for forming a pattern on a transparent substrate, said method comprising steps of: setting a substrate in a horizontal position where a surface of the substrate on which said thin film is formed faces upward, and said surface of the substrate and a surface of a sputtering target are in opposed position with a center axis of said target deviating from a center axis of said substrate surface, said sputtering target being in a single number, and sputtering the target while rotating said substrate around its center axis so as to form said thin film, wherein the target and the substrate are disposed so that opposite surfaces of said substrate and the target form an angle between 10 to 30 degrees, and so that a straight line passing through a center of the target and extended perpendicularly to a target surface does not pass through the substrate.