Abstract: A VDMOS device includes a wafer of semiconductor material having first and second opposed major surfaces. A drain region of a first conductivity type extends along the one major surface. A plurality of body regions of a second conductivity type is in the body region at the one major surface. Each body region forms with the drain region a body/drain PN junction, the intersection of which with the first major surface is in a closed path, preferably a hexagon. A plurality of spaced source regions of the one conductivity type are in each of the body regions with each source region being positioned opposite the space between two source regions in the adjacent body region. Each source region forms with the body region a source/body PN junction. A portion of each of the source/body PN junctions is adjacent to but spaced from its respective drain/body PN junction to form a channel region therebetween. An insulated gate is over the first major surface and the channel regions.

Abstract: A fast switch-off circuit for a conductivity modulated field effect transistor (COMFET) avoids the flow of destructive latch-up currents. A reduced-amplitude switch-off current is applied to the gate electrode of the COMFET during the initial portion of switch-off. When the source-to-drain voltage (V.sub.DS) of the COMFET has become larger than the range of low V.sub.DS voltage in which latch-up can occur for an increased-amplitude switch-off current being applied to the gate electrode of the COMFET, that increased-amplitude switch-off current is applied to the gate electrode of the COMFET.

Abstract: The preferred embodiment of the invention disclosed herein relates to an apparatus for testing semiconductor devices on a wafer containing a plurality of such devices. The apparatus includes a base having a support surface on which the semiconductor wafers can be located. The base further includes heater means for heating the surface and, thus, any wafers located thereon. Support stand means is associated with the base and extends above the support surface and a test probe unit connected in an electric test circuit is adjustably mounted on the support plate so that the probe unit is normal to and movable relative to the surface. Preferably, the test probe includes a tip that engages the wafer and this tip does not rotate when the position of the probe unit is adjusted.

Abstract: Accurate metering and dispensing of small quantities of abrasive material comprised of particles or powder, or both is accomplished by feed apparatus comprising a rotatable tubular member having a threaded interior surface for transporting the abrasive material through the tubular member in response to rotation of the member about the axis thereof. The discharge portion of the tube is particularly adapted to dispense frequent, small quantities of the material rather than less frequent larger quantities.