Patent ID: 6835434
Filing Date: 2004-12-28
Classification: C23C,G11B,Y10T

Abstract:
A method for manufacturing a disc-shaped optical recording medium comprising:a step of forming a disc-shaped substrate without a central hole for optical medium chucking, so that said disc-shaped substrate has a positioning guide formed in a non-sputtering surface being one surface of said disc-shaped substrate; at least one sputtering step of forming a film on a sputtering surface with sputtering of said disc-shaped substrate positioned by a carrier, while said positioning guide positions said disc-shaped substrate in place; said positioning guide is a circular recess formed at a center of said disc-shaped substrate during the step of forming the disc-shaped substrate without a central hole, said circular recess having a death not large enough to penetrate through the disc-shaped substrate in a thickness-wise direction; and a step of performing a region including said circular recess of said disc-shaped substrate after the sputtering step to form a central hole for optical medium chucking.