Abstract: A state changeable memory alloy and device employing same. The memory alloy is capable of changing from a first state to a second state in response to the input of energy, such as projected optical beam energy, electrical energy or thermal energy. The alloy has a first detectable characteristic when in the first state and a second detectable characteristic when in the second state. It is further characterized in that the first state comprises a single phase, and the second state comprises either: (1) a single phase having the same composition as the first phase or (2) a plurality of phases which have substantially similar crystallization temperatures and kinetics.

Abstract: A method and apparatus for direct, single beam, overwrite of new data over existing data in a phase change optical data storage device are disclosed. This eliminates the need for an intermediate erase step.

Abstract: Disclosed is an optical data storage device having a reversible, phase change data storage medium formed of (Sb.sub.2 Te.sub.3).sub.1-x (Sb.sub.2 Se.sub.3).sub.x, where x is from 0.18 to 0.43.

Abstract: Disclosed is a method and apparatus for depositing material on a substrate by periodically measuring an optical property of a region thereof, thereby obtaining a substantially continuous profile of the property for that region. The measured value of the property is compared with a predetermined value, and when the two values are substantially equal, deposition is terminated, thereby resulting in correct and reproductible layer thicknesses.

Abstract: Disclosed is a data storage device having a chalcogendata storage medium encapsulated along at least one surface, and preferably both surfaces, by a dielectric barrier layer. The dielectric is compositionally graded in oxygen content with respect to the chalcogen data storage medium. The dielectric is a substantially stoichiometric oxide in proximity to the chalocogen data storage medium, and a substantially non-stoichiometric suboxide remote from the chalcogenide data storage medium. The resulting data storage device is relatively moisture blocking and non-reactive with the chalcogendata storage medium. Also disclosed are methods of making and using the data storage device.

Abstract: Disclosed is a device and method for the storage and conversion of a light input into a corresponding output with light from another source. The device includes an improved liquid crystal light valve having as a photosensor layer a deposited memory semiconductor material which is reversibily convertible between a first stable, relatively high electrical resistance condition and a second stable, relatively low electrical resistance condition. Each change of state or condition will remain after cessation of the input until stimulated to reverse to the other state, thereby achieving a storage or memory function.

Abstract: Disclosed is an optical data storage device and a method of making the device. The device has a thin film of a multi-component, phase changeable, chalcogenide material. The thin film is prepared by vacuum deposition of a substantially non-convecting, multi-component, chalcogenide containing first source. The multicomponent source is converted to a non-condensed state, and the non-condensed material is deposited onto the substrate to form a deposit having substantial source/deposit compositional equivalence and the substantial absence of concentration gradients.

Abstract: There is disclosed a new and improved method for making a stamping master for video disk replication wherein a film of material which is reversibly convertible between two stable states, one having a high electrical conductivity and the other having a low electrical conductivity, is deposited on a substrate while in one of the states. The material is then imaged with information in coded form by converting selected areas of the film to the other state in a predetermined pattern corresponding to the coded information. The conversion can be accomplished by light, electromagnetic energy or heat.At this stage, an intermediate subassembly, composed of the imaged film on the substrate, is formed which can be read for accuracy by detecting the state of the selectively converted areas with respect to the rest of the film. Corrections can be made by converting the state of selected areas of the film as required.

Abstract: There is disclosed a new and improved apparatus for making a stamping master for video disk replication wherein a film of material which is reversibly convertible between two stable states, one having a high electrical conductivity and the other having a low electrical conductivity, is deposited on a substrate while in one of the states. The material is then imaged with information in coded form by converting selected areas of the film to the other state in a predetermined pattern corresponding to the coded information. The conversion can be accomplished by light, electromagnetic energy or heat.At this stage, an intermediate subassembly, composed of the imaged film on the substrate, is formed which can be read for accuracy by detecting the state of the selectively converted areas with respect to the rest of the film. Corrections can be made by converting the state of selected areas of the film as required.

Abstract: Selected areas of a layer comprising an imaging material in the form of a tellurium tetrahalide adduct of an aromatic amine, exemplified by a tellurium tetrachloride adduct of dimethyl aniline, which adduct is free from any diazo groups, in the presence of a spectral photosensitizer, are subjected to the imaging effect of imaging energy, and of development, advantageously of developing energy, causing a change in the tellurium-organic imaging material in the imaged areas accompanied by a change in the detectable characteristic of the imaging material in the imaged areas. The aforesaid imaging material is especially advantageously extended in a matrix of a polymeric or resinous film-forming material. The invention in its generally most advantageous form involves an imaging step employing imaging energy and producing a latent image, followed by a heat development step to produce the detectable recorded information or image.