A magnetic disk is provided which comprises a nonmetallic glass or glass ceramic substrate having one or more under layers, a magnetic layer applied over the under layers, and a hard carbon layer applied over the magnetic layer. A plurality of bumps are formed on the magnetic disk by applying a beam...http://www.google.com/patents/US20040265646?utm_source=gb-gplus-sharePatent US20040265646 - Laser textured magnetic disk
