Abstract: An apparatus and associated method used to control a disc drive having at least one disc and a transducer positionable relative to the disc by a motor. The motor receives energization through at least one power switch integrated on a semiconductor circuit. Temperature of the circuit is sensed proximate the power switch. A temperature signal is provided which is indicative of whether the sensed temperature meets one of a plurality of different threshold temperatures. The power switch is controlled in one of a plurality of different control modes based upon the temperature signal.

Abstract: An apparatus and associated method used to control a disc drive having at least one disc and a transducer positionable relative to the disc by a motor. The motor receives energization through at least one power switch integrated on a semiconductor circuit. Temperature of the circuit is sensed proximate the power switch. A temperature signal is provided which is indicative of whether the sensed temperature meets one of a plurality of different threshold temperatures. The power switch is controlled in one of a plurality of different control modes based upon the temperature signal.

Abstract: Reheating the cooled wafer product of the known method of forming thermal oxide surface passivation layers on GaAs crystal wafers, i.e. heating the wafer in contact with thermally vaporized As.sub.2 O.sub.3 in a substantially oxygen free closed vessel at a reaction temperature in excess of 450 degrees, from a temperature lower than the reaction temperature to a temperature higher than the reaction temperature and in the presence of free oxygen increases the compositional, physical and electrical uniformity of the surface layer.

Abstract: High quality native surface passivation dielectrics on Group III-Group V compound semiconductors are produced by thermal conversion of a surface layer having a specially provided composition. The electrical properties of these dielectrics meet the requirements for dielectric and passivation layers over semiconductor devices generally and in field effect devices in particular.

Abstract: III-V compound semiconductors having native dielectrics thereon which are thermally grown from special composition surface layers thereof are provided with reduced surface recombination velocities by proper selection of the surface layer's composition and extent of conversion to the dielectric.