Abstract: In a beam lithography operation the relative motion between a work piece and the exposure beam produces variations in linear speed at different regions of the work piece surface. For example, if a disk work piece rotates with a constant angular velocity (CAV) relative to the beam, the linear surface speed relative to the beam impact point increases in proportion to increasing radial distance of that point from the center of the disk. To provide uniform exposure dose, the duty cycle of pulses of the exposure beam are varied in accord with radial distance.

Abstract: A method of manufacturing a stamper/imprinter for use in patterning of a recording medium comprises sequential steps of: (a) providing a substrate/workpiece comprising a topographically patterned surface including a plurality of projections and depressions corresponding to a pattern to be formed in a surface of the recording medium; (b) forming a thin release layer in conformal contact with the topographically patterned surface by means of a dry process; (c) forming a thicker layer of a material in conformal contact with the thin passivation layer on the topographically patterned surface; and (d) separating the thicker layer of material from the topographically patterned surface to form therefrom a stamper/imprinter including an imprinting surface having a negative image replica of the topographically patterned surface, separation of the thicker layer of material from the topographically patterned surface being facilitated by the thin release layer formed by the dry process.

Abstract: The manufacture of magnetic disks for disk drives requires formation or servo tracks in a concentric pattern on the disk. Certain types of beam apparatuses for forming feature patterns on a disk shaped substrate, such as might be used in hard disk manufacture, however, provide spiral patterns. A ramp type deflection signal therefore is used to deflect the beam so as to form one circular pattern during each rotational cycle, and thereby convert the spiral pattern to a pattern comprising a series of circles.

Abstract: A plurality of redundant sets of servo data are recorded on a magnetic hard disk. The set meeting a predetermine criteria is employed when the hard disk is assembled into a hard disk drive. The determination of which set has the criteria may be conducted by the disk drive itself. The criteria may include a determination the set of servo data having meeting a minimum quality criteria or the fewest errors. The criteria may include a selection of a set of servo data having a specific pattern where the prerecorded sets may comprise a differing servo patterns that may be used by disk drives requiring specific servo patterns. The servo data are printed onto the hard disk by means of a stamper or mask having all the sets of servo data.

Abstract: A plurality of redundant sets of servo data are recorded on a magnetic hard disk. The set meeting a predetermine criteria is employed when the hard disk is assembled into a hard disk drive. The determination of which set has the criteria may be conducted by the disk drive itself. The criteria may include a determination the set of servo data having meeting a minimum quality criteria or the fewest errors. The criteria may include a selection of a set of servo data having a specific pattern where the prerecorded sets may comprise a differing servo patterns that may be used by disk drives requiring specific servo patterns. The servo data are printed onto the hard disk by means of a stamper or mask having all the sets of servo data.

Abstract: The manufacture of magnetic disks for disk drives requires formation or servo tracks in a concentric pattern on the disk. Certain types of beam apparatuses for forming patterns on disks, however, provide spiral patterns. A ramp type deflection signal therefore is used to deflect the beam so as to form one circular pattern during each rotational cycle, and thereby convert the spiral pattern to a pattern comprising a series of circles.