Abstract: A thermal gradient zone melting technique is employed to migrate an array of metal buttons through a body of semiconductor material to form high aspect ratio P-N junctions therein. Semiconductor devices embodying such P-N junctions are suitable for employment in X-ray and infrared detection and imaging. Each button preferably has the configuration of an equilateral triangle and the array preferably has a hexagonal configuration.

Abstract: A metastable mullite phase is formed in the physical structure of investment casting molds by employing alumina flour of a particle size less than 100 microns.

Abstract: An array of columnar structures are provided in a body of semiconductor material. The material of each columnar structure is recrystallized material of the body having solid solubility of dopant metal therein. Means are provided for connecting the columnar structures into two series electrical circuit arrangements to function respectively as the primary and secondary windings of a deep diode solid state transformer.

Abstract: A deep diode atomic battery is made from a bulk semiconductor crystal containing three-dimensional arrays of columnar and lamellar P-N junctions. The battery is powered by gamma rays and x-ray emission from a radioactive source embedded in the interior of the semiconductor crystal.

Abstract: A process for making shell investment molds for the casting and solidification of superalloys therein embodies preparing a primary slurry composition of a mixture of at least two different flour grain sizes of fused alumina and a silica binder. The flour grain sizes range from approximately 240 mesh to approximately 400 mesh, U.S. Standard or Tyler screen series.

Abstract: A multilayer passivation-encapsulation for a semiconductor element is provided by a suitable polymer layer disposed on the device and overcoated with a glass layer for hermeticity.

Abstract: The geometric configuration of a molten zone migrating through a solid body of semiconductor material during thermal gradient zone melting is maintained by simultaneous noncentro-symmetric and secondary rotation of the solid body.

Abstract: A process for making a deep diode atomic battery embodies thermal gradient zone melting techniques for fabricating the structure thereof. Thermal gradient zone melting may also be employed to provide the battery with a radioactive source for energizing the battery.

Abstract: One region of a large area semiconductor power diode comprises recrystallized semiconductor material formed in situ, and joined to a second region, by temperature gradient zone melting.

Abstract: An improved method of initiating the moving of a molten zone of a metal-rich semiconductor material through a solid body of the same semiconductor material embodies the sintering of the metal to the surface of the body. The sintering process enables one to migrate two or more intersecting "wires" simultaneously as well as three wires intersecting at a common point of origin.

Abstract: A solution of potassium hydroxide is employed to remove the reaction products of aluminum migrated through silicon-semiconductor material by thermal gradient zone melting processing.

Abstract: Annular regions of a predetermined type conductivity are produced in a body of semiconductor material by a temperature gradient zone melting process embodying both noncentro-symmetric rotation of the body as well as secondary rotation of the body about its vertical axis.

Abstract: Metal wires of widths as small as 10 microns are successfully migrated by thermal gradient zone melting processing as a molten zone through a body of semiconductor material. The metal wires are migrated to a preselected depth without use of oxide masking and/or etched grooves when the planar orientation of the surface of the body is (100).

Abstract: Isolation junctions in semiconductor devices are formed by selected regions of specified conductivity wherein each region has a substantially uniform thickness and resistivity throughout the region. The material of the selected regions is recrystallized semiconductor material with solid solubility of the dopant impurity.

Abstract: A deep buried electrical layer is provided in a semiconductor device by thermal gradient zone melting.

Abstract: Deep level impurities such, for example, as gold, platinum, silver, nickel and copper, are introduced into selected regions of semiconductor devices by directional solidification to reduce the charge recombination lifetime and therefore the turn-off time of the device.

Abstract: A semiconductor controlled rectifier has a lamellar body of semiconductor material of at least one group of four alternate first and second regions of opposite type conductivity. The second regions are made from recrystallized semiconductor material of the first regions and contain a sufficient level of concentration of a dopant impurity to impart thereto the opposite type conductivity. It is recrystallized material with solid solubility of the impurity. The controlled rectifier is turned on and off by either a control electrode or a source of illumination.

Abstract: A droplet of alloy material containing at least two semiconductor dopant type elements, each of which has a different ratio of diffusivity, is thermomigrated by a thermal gradient zone melting process through a body of semiconductor material leaving behind a recrystallized region of semiconductor material containing at least two dopant materials therein. Following thermomigration of the droplet, the body of semiconductor material is subjected to a post-thermomigration heat treatment at an appropriate temperature to allow the dopants in the region produced by thermomigration to diffuse substantially perpendicular to that region into the remaining material of the body. The slower diffusing dopant species is largely left behind in the region to form a region of conductivity type determined by the slower diffusing species while the faster diffusing species will diffuse outward and form an annulus around the recrystallized region of a conductivity type determined by the faster diffusing species.

Abstract: The minority carrier lifetime is drastically reduced in an integrated semiconductor power device by introducing deep level impurities such, for example, as gold, silver, platinum, nickel and copper into selected regions of the device by Thermal Gradient Zone Melting processing.

Abstract: Deep finger diodes in a body of semiconductor material are fabricated by a thermal gradient zone melting process. A liquid wire or droplet is migrated into the body through one surface to a depth less than the thickness of the body. The migration of the liquid wire or droplet is reversed to remove the wire or droplet from the body leaving a recrystallized material of the body having solid solubility of a material therein.