Abstract: A technique for optically monitoring the undercutting of a layer of material being selectively etched beneath a pattern of masking material in an etchant comprises forming on a layer of the material being etched a diffraction grating pattern including spaced strips of masking material having a strip width W, exposing the diffraction grating pattern, while positioned in the etchant, to a beam of monochromatic light, whereby the grating pattern together with the layer of material therebeneath functions as a relief pattern which diffracts the beam of light into diffracted beams of various orders, and then monitoring certain of said diffracted beams to determine when a sharp decrease in the intensity thereof occurs, such a sharp decrease indicating an undercutting equal to a distance of W/2.

Abstract: An integrated circuit device comprises a layer of semiconductor material on an insulating substrate. At least two spaced-apart circuit components, such as field-effect transistors, are formed in the layer of semiconductor material. The circuit components are electrically isolated from each other by a method of (1) forming a layer of insulating material over the layer of semiconductor material and between the circuit components, (2) forming a layer of electrically conductive material over the layer of insulating material, and (3) providing bias means between the layer of conductive material and the layer of semiconductor material so as to deplete completely a region in the layer of semiconductor material opposite to the layer of conductive material and between the circuit components.

Abstract: A semiconductor wafer vacuum chuck used as part of a photographic wafer-alignment machine for performing contactless photolithography has integral spacer means disposed on a substantially planar surface thereof for mechanically maintaining a fixed distance between portions of a wafer positioned adjacent the spacer means and the surface of the wafer chuck, whereby a controlled separation is provided between a surface of the wafer and a photographic mask overlying the surface of the wafer upon the application of a vacuum to the surface of the wafer chuck.

Abstract: A layer of silicon dioxide such as used in an MOS gate dielectric, is treated, after growth, to prevent deleterious effects resulting from any mobile impurity ions therein. An ionic fluoride compound is applied to one surface of the layer of silicon dioxide. A corona discharge is then directed from a negative electrode of a pair of electrodes of opposite polarity onto the fluoride compound to drive the fluoride ions into the layer. The layer is then washed and annealed.

Abstract: Certain electrical characteristics of a semiconductor device which includes a body of semiconductor material are improved by exposing the semiconductor device to a substantially water vapor free atmosphere of chlorine and heating the device in this atmosphere.

Abstract: An electrostatic charge pattern is developed into a visual image with the aid of a current-sensitive recording element that is disposed against one face of an array of a plurality of field-effect devices. The charge pattern, on an electrically insulating film, is disposed against an opposite face of the array. An electrical circuit, connected to source and drain regions of the field-effect devices, causes current to flow in each of the devices in accordance with the intensity of each elemental portion of the charge pattern adjacent a respective channel region in each of the devices. The electrical current causes a color change in the recording element in accordance with the intensity of the current flowing therethrough.

Abstract: A heat-sink assembly adapted for use with a high-power stud-mounted semiconductor device comprises a heat-dispersing arm having one end securely attached to a circuit board and the other end shaped for semipermanent connection and thermal coupling to a heat-conductive stud. The arm is sufficiently bendable to allow displacement thereof from above the surface of the device mounted on the circuit board for removal of the device from the circuit board after disconnecting the other end from the stud while keeping the one end securely attached to the circuit board. The heat-sink assembly may further comprise means for semipermanently connecting the other end of the arm to the stud and retaining the other end in intimate thermal contact therewith.

Abstract: Raised electrical contacts are electroplated on selected previously metallized contacts of a semiconductor device. Each metallized contact is on a surface of a separate mesa, respectively, of the device and extends in a cantilever manner beyond the surface of the mesa. The electroplating of the raised electrical contacts is accomplished by the steps of (1) depositing a layer of a metal over the device, (2) applying a photoresist over the layer of the metal, (3) defining openings in the photoresist over areas of the metallized contacts where the raised contacts are to be formed, and (4) electroplating the raised contacts on the metallized contacts through the openings, using the layer of the metal as an electrode in an electroplating system.

Abstract: Epitaxial layers of silicon, having thicknesses of at least about 25 .mu.m, are grown on the (100) or (111) planar surfaces of silicon substrates by the vapor deposition of silicon from the reaction of dichlorosilane and hydrogen gas in a reactor furnace. Good epitaxial layers of silicon of substantially uniform thicknesses are formed on the substrates when the growth rate of the epitaxial layer is between about 5 and 20 .mu.m/minute in the reactor furnace, and the latter is heated to a temperature of between about 1050.degree. and 1200.degree.C.

Abstract: A fluid flow measuring system utilizing semiconductor devices as heating and temperature sensitive elements produces an electrical output signal which is linearly proportional to the rate of flow of a fluid and which automatically compensates for changes in fluid density.

Abstract: A planar bipolar transistor is made by the successive ion implantations of selected atoms into selected regions of a layer of doped single-crystal silicon on an insulating substrate, such as sapphire or spinel. The silicon layer is epitaxially grown, has a thickness of between 0.5 and 5 .mu.m, and is formed in two strata of different resistivities. A collector contact well is ion implanted into the upper stratum and annealed to diffuse it into the lower stratum of lower resistivity. The transistor is isolated, as a mesa, on the substrate; and an edge-guard region is ion implanted through the periphery of the mesa, except in the region of the emitter-base junction.