Abstract: Optical disc stampers, methods of manufacturing the optical disc stampers, systems for manufacturing the optical disc stampers, and methods of replicating optical discs using the stampers are disclosed. The optical disc stamper is formed directly on a substrate that supports a patterning material including at least one layer of a first material and at least one layer of a second material. The first and second materials can include a metal and semiconductor. The patterning material is exposed to energy in selected areas. Unexposed areas of the patterning material are then removed, resulting in an optical disc stamper. The first and second materials can form an amorphous alloy in the exposed selected areas that remains after removal of the unexposed patterning material. The optical disc stamper can be used in the replication of optical data storage discs. Also disclosed arc systems for practicing the methods to produce optical data storage disc stampers.

Abstract: A dual layer pre-recorded optical disc includes a transparent substrate, a partially reflective layer, a transparent spacer layer, and a highly reflective layer. One pattern of data pits is provided on the substrate, adjacent the partially reflective layer, and another pattern of data pits is provided on the spacer layer, adjacent the highly reflective layer. The transparent spacer layer comprises at least two sublayers. The partially reflective layer may be made of silicon carbide. A substrate-incident beam can be used to read data encoded in either data pit pattern depending on which layer the laser is focused upon. The dual layer disc has twice the data storage capacity of conventional single layer discs.

Abstract: A stable amorphous rare earth oxide, such as Y.sub.2 O.sub.3, including a stabilizer, such as carbon, silicon carbide, or hafnium oxide. The stable amorphous rare earth oxide can be used in a dielectric layer in a magneto-optical recording medium.

Abstract: A dual layer pre-recorded optical disc includes a transparent substrate, a partially reflective layer, a transparent spacer layer, and a highly reflective layer. One pattern of data pits is provided on the substrate, adjacent the partially reflective layer, and another pattern of data pits is provided on the spacer layer, adjacent the highly reflective layer. The partially reflective layer may be made of silicon carbide. A substrate-incident beam can be used to read data encoded in either data pit pattern depending on which layer the laser is focused upon. The dual layer disc has twice the data storage capacity of conventional single layer discs.

Abstract: A magneto-optic recording medium including a transparent substrate and a magneto-optic stack provided thereon. The stack includes a plurality of magneto-optic film layers less than 10 nm thick. Adjacent magneto-optic film layers are separated by dielectric layers consisting essentially of Y.sub.2 O.sub.3.

Abstract: A dual layer pre-recorded optical disc includes a transparent substrate, a partially reflective layer, a transparent spacer layer, and a highly reflective layer. One pattern of data pits is provided on the substrate, adjacent the partially reflective layer, and another pattern of data pits is provided on the spacer layer, adjacent the highly reflective layer. The partially reflective layer may be made of an alloy of gold and silver having a general formula Au.sub.x Ag.sub.y, where 15<x<40 and 60<y<85. A substrate-incident beam can be used to read data encoded in either data pit pattern depending on which layer the laser is focused upon. The dual layer disc has twice the data storage capacity of conventional single layer discs.

Abstract: A dual layer pre-recorded optical disc includes a transparent substrate, a partially reflective layer, a transparent spacer layer, and a highly reflective layer. One pattern of data pits is provided on the substrate, adjacent the partially reflective layer, and another pattern of data pits is provided on the spacer layer, adjacent the highly reflective layer. The partially reflective layer may be made of silicon carbide. A substrate-incident beam can be used to read data encoded in either data pit pattern depending on which layer the laser is focused upon. The dual layer disc has twice the data storage capacity of conventional single layer discs.

Abstract: Electrically conductive sputtering target comprising yttria and amorphous carbon, a method of making the same, and a method of using the same.

Abstract: A method of sequential deposition of source materials onto a web substrate. A substrate transfer mechanism imparts continuous movement of a substrate past a plurality of deposition sources during vapor deposition of deposition source materials. Every portion of the substrate is exposed to deposition fluxes from the deposition sources in an alternating periodic manner. The number of source exposures is greater than the number of sources.

Abstract: A multilayer optical recording medium comprising a substrate, an optional dielectric layer, a first recording layer, a second recording layer, and an optional protective layer. The first recording layer comprises an alloy of a metal and at least one doping element, and the second recording layer comprises a semiconductor. A binary combination of the metal of the first recording layer and the semiconductor of the second recording layer exhibits eutectic phase equilibria.

Abstract: A thermomagnetic recording system achieves high areal bit density by combining the high linear bit density of magnetic recording and the high track density typical of magneto-optic recording. The system employs a medium which comprises a ferrimagnetic recording material having a compensation temperature approximately equal to ambient operating temperature, yet small coercivity and high saturation magnetization at elevated temperatures. A source of heat (preferably a laser) controls the magnetic properties of the material. Data is recorded and played back with high performance magnetic recording heads, producing direct overwrite capability, at temperatures less than the Curie point of the material.