Abstract: An apparatus for controlling data read/write between a hard disk and a hard disk controller is disclosed. The hard disk includes a disk for storing data, multiple read/write heads for reading or writing data onto the disk in accordance with a read request or write request from a requesting device, a non-volatile memory for storing control data in relation to reading data from the disk or writing data to the disk, and a controller for sending the control data to the requesting device in response to a read request or a write request from the requesting device before reading data or writing data.

Abstract: In one illustrative example, a method for use in reducing Repeatable Run Out (RRO) error in a data storage device involves obtaining an RRO measurement for each track of a limited number of N disk tracks; characterizing the RRO measurement for each track with real and imaginary values by performing a discrete Fourier transform (DFT) calculation on each RRO measurement; performing a least-squares fit on all of the real values to identify a first set of (n+1) coefficients of an nth-order polynomial function which is a function of disk track r and representable in the form Ai(r)=anrn+a(n?1)r(n?1)+ . . . +a1r+a0; and performing a least-squares fit on all of the imaginary values to identify a second set of (n+1) coefficients of an nth-order polynomial function which is a function of disk track r and representable in the form Bi(r)=bnrn+b(n?1)r(n?1)+ . . . +b1r+b0.

Abstract: The present invention involves a recordable disk having a first plurality of S1 servo sample wedges in a first servo zone at an outermost position on the disk, a second plurality of S2 servo sample wedges in a second servo zone which is radially adjacent the first servo zone, and a third plurality of S3 servo sample wedges in a third servo zone which is radially adjacent the second servo zone. The S1 servo sample wedges of the first plurality are equally spaced apart circumferentially around the disk by a first angle ?1, the S2 servo sample wedges of the second plurality are equally spaced apart circumferentially around the disk by a second angle ?2=?1*N1, and the S3 servo sample wedges of the third plurality are equally spaced apart circumferentially around the disk by a third angle ?3=?2*N2.

Abstract: A method for fabricating a transducer with landing pads without edge fences is described. Preferably an adhesion layer and then the pad layer are deposited in voids in a photoresist. The thickness of the masking layer on the surface of the pad layer should be sufficient to protect pad layer during the subsequent ashing step, but the thickness of the masking material at the sidewalls on the pad layer fences should be thin enough so that the fences are not protected during ashing. After stripping the photoresist material, the structure is ashed preferably by an oxygen-containing plasma. The ashing process, with assistance from mechanical abrasion, removes the fence structures on the pad layer, since the thinner masking layer at the sidewalls provides less protection to the fence structures than is provided to the bulk of the pad layer where the masking layer is thicker.

Abstract: A thin film magnetic media structure comprising a pre-seed layer CrTi is disclosed. The CrTi pre-seed layer presents an amorphous or nanocrystalline structure. The preferred seed layer is RuAl. The use of the CrTi/RuAl bilayer structure provides superior adhesion to the substrate and resistance to scratching, as well as, excellent coercivity and signal-to-noise ratio (SNR) and reduced cost over the prior art.