Patent ID: 9376336
Filing Date: 2016-06-28
CPC Classification: C03B,C30B,Y02P,Y10T

Claim Text:
1. A method for producing a quartz glass crucible, comprising the steps of: preparing a crucible base material that is made of quartz glass and has a crucible shape; producing a synthetic quartz glass material by a direct process or a soot process; processing the synthetic quartz glass material into a crucible shape without pulverizing the synthetic quartz glass material; and welding the synthetic quartz glass material processed into the crucible shape to an inner surface of the crucible base material wherein the welding is performed as the same time by the application of heat performed when the synthetic quartz glass material processed into the crucible shape is placed inside the crucible base material, the inside of the synthetic quartz glass material is filled with polycrystalline silicon, and the polycrystalline silicon is melted in a silicon single crystal pulling apparatus.