| Patent application number | Description | Published |
|---|
| 20080231984 | Apparatus and method to minimize amplitude variations associated with media/head response characteristics in servo writing of perpendicular magnetic recording - A servo writer that writes servo information onto a disk of a hard disk drive. The writing of the servo can be synchronized by a clock track that contains a clock read back signal. The clock read back signal is differentiated by a differentiator circuit. A clamping circuit clamps the clock read back signal to minimize signal ringing, undershoot and overshoot phenomena in the signal. | 09-25-2008 |
| 20080316648 | Nanocryalline structured co-based alloy intermediate layer (IL) replacing ru layer in perpendicular magnetic recording media for hard disk drive - A disk for a hard disk drive. The disk includes a first magnetic layer and a second magnetic layer. An intermediate layer consisting of cobalt and titanium is located between the first and second intermediate layers. The intermediate layer creates a finer grain size and larger crystalline anisotropy in the second magnetic layer, characteristics that are desirable when used with a perpendicular recording head. | 12-25-2008 |
| 20090046387 | Patterned media with low switching filled and adjacent track encroachment (ATE) using ECC (exchange coupled composite) media - A patterned disk for a hard disk drive. The patterned disk includes a hard magnetic layer over a substrate. The disk further includes an exchange control layer adjacent to the hard magnetic layer and a soft magnetic layer adjacent to the exchange control layer. The hard and soft magnetic layers are arranged into a plurality of dots that are separated by a non-magnetic material. The soft and hard magnetic layers combined with the exchange control layer creates an exchange coupled composite that has a relatively low switching field and favorable thermal stability. The low switching field improves reliability when the disk is used in perpendicular recording. | 02-19-2009 |
| 20090047547 | Nanopatterning of disk media with flash sacrificial layer in block copolymer lithography - A method for fabricating a patterned disk of a hard disk drive. The method includes forming a layer of magnetic material over a substrate and then forming a sacrificial flash layer over the layer of magnetic material. A co-polymer material is formed over the sacrificial flash layer and then a plurality of magnetic dots separated by a non-magnetic material are formed in the magnetic layer. The flash layer is preferably a FePt material with a non-magnetic Ag or Cu based alloy. Such material not only provides good adhesion between the co-polymer and magnetic layers but also diffuses into the grains of the magnetic material. The diffusion of the non-magnetic flash layer between the grains of the magnetic material reduces magnetic cross-talk and improves the signal to noise ratio of the disk. | 02-19-2009 |
| 20090237835 | Switching field controlled (SFC) media using anti-ferromagnetic thin layer in magnetic recording - A patterned disk for a hard disk drive. The patterned disk includes an anti-ferromagnetic layer of Fe | 09-24-2009 |
