Abstract: A bump disk for accurate glide calibration has a new type of glass laser melt bumps that give the same signal amplitudes as conventional AlMg laser melt bumps for the same bump height. The present invention provides a solution to switch the calibration bumps from AlMg to glass, and can be used in disk manufacturing lines to save 30% on the cost of hard disks from inaccurate glide certification processes. The solution is to trim or burnish away loose and/or high particles on production disks before the glide tests. This additional processing step causes the responses from the glass bumps to become very similar to those of the AlMg bumps, thereby enabling glass and AlMg disks to become materially compatible.

Abstract: The present invention is a read/write head for writing information to magnetic media and reading information from magnetic media. It includes a write head element for writing information onto magnetic media, a read head element for reading information from the magnetic media, and an electromagnetic field shield element that is disposed between the write head element and the read head element. The shield functions to shield the read head from electromagnetic field energy created by the write head element. An enhanced second embodiment includes an electrical circuit element that is disposed proximate the read head element that functions to generate an electromagnetic field at the read head element that is generally oppositely directed to the electromagnetic field generated by the write head element to reduce the total electromagnetic field that the read head element is exposed to during a writing operation.

Abstract: The thin film magnetic disk of the present invention includes a non-metallic substrate having a seed layer deposited on the substrate, an underlayer deposited upon the seed layer composed of a chromium alloy having a relatively high oxygen concentration portion of from 2,000 ppm to 20,000 ppm and preferably approximately 4,000 ppm to 12,000 ppm, followed by a relatively low oxygen concentration portion of from 0-2,000 ppm, and preferably from 500 ppm to 1,500 ppm and a magnetic layer that is deposited upon the underlayer. The underlayer total thickness is in the range of from approximately 250 Å to approximately 700 Å with a preferred thickness of approximately 450 Å, wherein approximately half of the underlayer thickness is the high oxygen concentration portion and half is the low oxygen concentration portion.

Abstract: The present invention is a read/write head for writing information to magnetic media and reading information from magnetic media. It includes a write head for writing information onto magnetic media, a read head for reading information from the magnetic media, and an electrical circuit element that is disposed proximate the read head that functions to generate an electromagnetic field at the read head that is generally oppositely directed to the electromagnetic field generated by the write head. The method for operating the read/write head in a hard disk drive, includes the steps of writing data onto a hard disk, while simultaneously generating an electromagnetic field at the read head that is directed oppositely to the electromagnetic field generated by the write head.

Abstract: The burnishing head for hard disk processing includes a solid body having generally rectangular surfaces, including an upper surface, a burnishing pad surface, a front surface, a rear surface and two side surfaces. A plurality of burnishing pads are disposed upon the burnishing pad surface. The pads are shaped such that each pad has a burnishing edge that is generally parallel to said front surface and therefore orthogonal to the direction of media travel. The burnishing pads are preferably configured such that one frontward leading pad is centrally disposed proximate the front surface of the head, followed by two middle pads that are disposed in a spaced apart relationship. A single centrally disposed rear middle pad is formed behind the two middle pads, and two rear pads are disposed in a spaced apart relationship at the rear surface of the head. In the preferred embodiment the pads are generally triangular in shape and the outer surface of the leading and rearward pads is tapered.

Abstract: The disk burnishing process is conducted with a contact flying burnishing head wherein the leading edge of the burnishing head is disposed above the surface of the disk, while the trailing edge of the burnishing head makes contact with the surface of the disk. The contact flying configuration of the burnishing head is obtained by controlling the rotating disk RPM in conjunction with the burnishing head design characteristics.

Abstract: The hard disk testing and certifying device of the present invention includes a spin stand to rotate a disk to be tested. A single read/write head, including both a write head and a read head is mounted upon an armature which movably supports the read/write head. The device includes a computerized control system and signal processing system that provides write signals to the write head and receives and processes read head signals from the read head. In the preferred embodiment the read/write head simultaneously provides write signals to the disk and receives read signals from the disk. Preferably, the read/write head functions continually and the certification testing is conducted utilizing a spiral path. In the preferred read/write head the read head is disposed behind the write head and an electromagnetic field shield is disposed between them to reduce electromagnetic field interference between the write head and the read head during simultaneous operation.

Abstract: A method and apparatus for precise measurement of pressure dependence of head fly height using transitional thermal signals is disclosed. A slider is positioned relative to a rotating a disk having at least one laser bump. Calibration data is gathered by decreasing the pressure and measuring the fly height until a contact positive TA signal is detected. A non-contact negative TA signal is then normalized using the gathered calibration data. The TA signal amplitude may then be used to ascertain the fly height and pressure for a head.

Abstract: A method of fabricating a thin film magnetic disk including depositing a seed layer of a refractory metal such as tantalum, Cr, Nb, W, V, or Mo and a reactive element such as N or O; depositing a nonmagnetic underlayer onto the seed layer; and depositing a magnetic layer is disclosed. Also disclosed is a thin film magnetic disk having a substrate; a seed layer comprising tantalum and at least about 1 atomic-% of nitrogen or oxygen; an underlayer comprising Cr or an alloy of chromium deposited onto the seed layer, the underlayer preferably having a preferred orientation of [200]; and a magnetic layer deposited onto the underlayer, the magnetic layer preferably having a preferred orientation of [11{overscore (2)}0]. Also disclosed is a disk drive using the thin film magnetic disk of the invention.

Abstract: A thin film disk and a disk drive using the thin film disk are described. The disk has an onset layer between the underlayer and the boron containing magnetic layer, for example. The onset layer of the invention is useful because the boron containing magnetic layer material resists being deposited with the C-axis in plane. The onset layer material is selected to promote an in-plane C-axis orientation. When a boron containing magnetic layer is deposited on the onset layer the resulting in-plane PO is improved. The preferred onset layer is of hexagonal closed pack structured material which may be magnetic or nonmagnetic. Materials which are usable for the onset layer include a wide range of pure elements and cobalt alloys such as CoCr, CoPtCr, CoPtCrTa and CoCrB.