Patent ID: 8092281
Filing Date: 2012-01-10
Classification: B24B

Abstract:
1. A polishing head provided at least with an annular rigid ring, a rubber film bonded to the rigid ring with a uniform tension, a mid plate joined to the rigid ring and forming a space together with the rubber film and the rigid ring, and an annular template provided concentrically with the rigid ring in a peripheral portion on a lower face part of the rubber film and having an outer diameter larger than an inner diameter of the rigid ring, in which a pressure of the space can be changed by a pressure adjustment mechanism, a back face of a work is held on the lower face part of the rubber film, and a surface of the work is brought into sliding contact with the polishing pad attached onto a turn table for performing polishing, wherein an inner diameter of the template is smaller than an inner diameter of the rigid ring, and a ratio between an inner diameter difference between the rigid ring and the template and a difference between the inner diameter and an outer diameter of the template is 26% or more and 45% or less.