Abstract: A process and apparatus for bonding together two layers of dissimilar material, yielding a composite structure which is substantially stress-free at a selectable reference temperature and reference isostatic pressure, which includes providing a first layer and a second layer; determining a critical line for the first layer and second layer in a pressure-temperature plane wherein a location of the critical line depends on the selectable reference temperature and reference isostatic pressure and depends on coefficients of thermal expansion and bulk moduli material constants of the first layer and the second layer, wherein the critical line sets forth a plurality of temperature-pressure pairs at which the composite structure will be substantially stress-free; controlling a temperature and an isostatic pressure during bonding such that the temperature and the isostatic pressure represent a point on the critical line; bonding the first layer and the second layer at the temperature and the isostatic pressure; and r

Abstract: A multi-layer structure including a first layer; a second layer, with a coefficient of thermal expansion different than a coefficient of thermal expansion of the first layer, a bulk modulus different than a bulk modulus of the first layer and a thermal conductivity different than a thermal conductivity of the first layer; a bonding layer, having an isostatic pressure versus temperature curve with one of the first layer and the second layer which is substantially similar to an isostatic pressure versus temperature curve of the first layer and the second layer, such that a substantially stress-free bond is formed between the first layer and the second layer; wherein the first layer, the second layer, and the bonding layer are arranged as a sandwich, with the bonding layer in between the first layer and the second layer.

Abstract: A process and apparatus for bonding together two layers of dissimilar material, yielding a composite structure which is substantially stress-free at a selectable reference temperature and reference isostatic pressure, which includes providing a first layer and a second layer; determining a critical line for the first layer and second layer in a pressure-temperature plane wherein a location of the critical line depends on the selectable reference temperature and reference isostatic pressure and depends on coefficients of thermal expansion and bulk moduli material constants of the first layer and the second layer, wherein the critical line sets forth a plurality of temperature-pressure pairs at which the composite structure will be substantially stress-free; controlling a temperature and an isostatic pressure during bonding such that the temperature and the isostatic pressure represent a point on the critical line; bonding the first layer and the second layer at the temperature and the isostatic pressure; and r

Abstract: A process and apparatus for bonding together two layers of dissimilar material, yielding a composite structure which is substantially stress-free at a selectable reference temperature and reference isostatic pressure, which includes providing a first layer and a second layer; determining a critical line for the first layer and second layer in a pressure-temperature plane wherein a location of the critical line depends on the selectable reference temperature and reference isostatic pressure and depends on coefficients of thermal expansion and bulk moduli material constants of the first layer and the second layer, wherein the critical line sets forth a plurality of temperature-pressure pairs at which the composite structure will be substantially stress-free; controlling a temperature and an isostatic pressure during bonding such that the temperature and the isostatic pressure represent a point on the critical line; bonding the first layer and the second layer at the temperature and the isostatic pressure; and r

Abstract: A process for fabricating a monolithic integrated circuit having matched semiconductor devices and P-N junction isolation regions, with the collector regions for the semiconductor devices of one polarity type and the isolation regions being formed by up-diffusing impurities from a selected surface of a substrate of one conductivity type though an epitaxial layer of opposite conductivity type formed thereon, so that such collector regions are surrounded by material of opposite conductivity type, and the P-N junction isolation regions selectively isolate semiconductor devices of opposite polarity type from other circuit elements, wherein such collector regions and P-N junction isolation regions have retrograded impurity concentration profiles.

Abstract: Disclosed is an optical coupler apparatus comprising a photo-emissive device and a photo-sensitive device responsive to the wavelengths emitted by the source. The devices are mounted on frame leads with their major faces opposed and spaced apart. The optical devices and a substantial portion of the supporting frame leads are then encapsulated in a molded body of substantially electrically non-conductive material which is substantially transparent to the operative wavelengths of the optical devices.The transparent material not only fills the space between the optical devices but also provides structural support for the leads. The transparent material is then covered with an opaque coating or an additional body of opaque material molded over the body of transparent material.