Abstract: A method for scanning the top surface of a semiconductor wafer prevents damage to the wafer (11) by ensuring that the laser beam (13) does not cross over the edge (11a) of the wafer during the scanning process nor approach within one (1) to two (2) millimeters to the edge of the wafer.

Abstract: A microprocessor comprising: an address data path; an arithmetic logic unit data path, said data paths being capable of simultaneous operation; an information bus; a shared bus register; a shared input multiplexing apparatus for selectively transferring address and data information from said information bus and data information from said arithmetic logic unit data path to said shared bus register; and a multiplexing apparatus for transferring information from said shared bus register to said arithmetic logic unit data path and to said information bus via said address data path whereby said shared bus register is selectively useable as a memory data register, a memory address register and a temporary or "scratch-pad" register during normal operation of the microprocessor; and further comprising; a programmable logic array containing a sequence of microinstructions and apparatus connected thereto for testing the operability of the microprocessor.

Abstract: A method of removing bulk impurities from a semiconductor wafer is described comprising the steps of lapping the front and back surfaces of the wafer to remove 35 to 40 microns of material therefrom and to make the surfaces parallel, heating the wafer at a predetermined temperature preferably equal to or above the highest temperature to be used in subsequent device fabrication, etching the front and back surfaces of the wafer to remove 35 to 40 microns of material therefrom and thereafter polishing the front surface of the wafer for removing 20 microns of material therefrom. By means of the above process the number of surface defects caused by strain producing centers in the crystal lattice of the wafer is reduced from 500,000 defects per square centimeter to less than 1,000 defects per square centimeter.

Abstract: An address gate for a random access memory includes a pair of emitter-coupled and collector-coupled transistors, and another transistor emitter-coupled to the pair of transistors. Complimentary outputs are read at the coupled emitters of the pair of transistors and the collector of the other transistor respectively, there being an input signal applied to the base of one of the pair of transistors, and a control signal applied to the base of the other of the pair of transistors, which overrides the operation of one of the pair of transistors when the control signal is in its high state.

Abstract: Diagnostic testing of a charge coupled device is facilitated by interconnecting the reference node of the sense amplifier for each data block in the CCD device with a probe contact on the device, thereby eliminating the need for applying a microprobe to the sensitive reference node. Reference voltages under different operating conditions can be evaluated by measuring the device generated reference voltage or by applying variable reference voltages through the probe contact to the reference node.

Abstract: A process and resulting structure are disclosed for forming vias in integrated circuit structures using metal silicide interconnections. A lower conductor is formed by sequentially depositing silicon and a refractory metal which reacts with the silicon to create a layer of metal silicide. A subsequent layer of silicon is deposited on the surface of the metal silicide. This layer of silicon is insulated from overlying layers by forming insulating material over desired regions of the layer of silicon. A second layer of metal is then deposited across the structure. In openings in the insulating material the metal reacts with the second layer of silicon to form a via of metal silicide. A final layer of silicon may be deposited to convert any remaining metal in the second layer of metal to metal silicide, and the structure annealed to lower its resistivity.

Abstract: Apparatus for amplifying output signals from a charge coupled area imaging device includes a resettable first floating gate amplifier connected to sense charge in the charge coupled device output register at a first location, a second floating gate amplifier connected to sense charge in the charge coupled device output register at a second location, and a charge limiting well disposed between the first location and the second location to remove charge in excess of a desired amount before the output signals are sensed at the second location. The dual preamplifiers permit optimization of the output signals from the charge coupled imaging device for two substantially different light levels by providing a substantially lower noise equivalent input signal level from the second preamplifier.

Abstract: Circuitry for presetting a bipolar random access memory includes switching transistors, responsive to an applied memory preset signal, for opening the circuit between the memory word lines and their respective current sources, for applying a positive voltage to the bottom word lines, for breaking the circuitry between bit line clamping circuits and their respective power sources, and for grounding the bit line pairs to drain all current from the bit line circuits. The preset circuitry also includes read/write control transistors coupled between each bit line and a V.sub.cc source for steering the set of the memory cells upon removal of the preset signal.

Abstract: A probe is disclosed for the nondestructive inspection of the interior walls of cylindrical recesses, comprising an elongated shaft having an ultrasonic transducer mounted thereon a predetermined distance from the longitudinal axis of the shaft and oriented for directing the axis of radiation of ultrasonic energy emanating from the transducer outwardly in a plane perpendicular to the longitudinal axis of the shaft. In another embodiment, the probe comprises a shaft having a lateral extension whereon a first ultrasonic transducer is mounted at a predetermined distance from the longitudinal axis of the shaft and is oriented for directing the axis of radiation of ultrasonic energy emanating therefrom parallel to a line formed by the intersection of planes perpendicular to the longitudinal axes of the shaft and lateral extension.

Abstract: A system is provided inside a turbomachine for controlling operational clearance between a turbine rotor and a surrounding turbine shroud. The system comprises a plurality of control rings, integrated into the turbine casing, that are thermally expanded and contracted to control radial positioning of the turbine shroud. Compressor air is directed through internal passages in the rings to cause the expansion and contraction. The system utilizes the pressure and temperature of compressor air, in combination with size, location, and structure of the control rings to match thermal growth of the control rings and turbine shroud to thermal growth of the turbine rotors, thereby controlling clearance.

Abstract: The apparatus includes a light source for directing a measuring beam toward a workpiece and a photo detector positioned to receive a portion of the measuring beam reflected from the workpiece. A beam splitter is positioned between the light source and the workpiece to reflect a portion of the light source measuring beam to a monitor photo detector. The monitor photo detector receives the beam splitter reflected beam and provides an output signal representative of the position of the beam splitter reflected beam, and hence, the position of the light source with respect to an idealized position. In one embodiment, the photo detector develops a monitor output signal representative of the deviation between an Idealized Centerline and an Actual Centerline of the light source. The monitor output signal may be employed for display purposes.

Abstract: The apparatus includes a first connecting link having a pair of axially opposing ends with one of the ends being coupled through a uniball to a drive portion of an actuator. A second connecting link includes a pair of axially opposing ends. One of the ends of the second connecting link is coupled to a driven portion, e.g., a butterfly valve. Coupling means, including a mating plug and socket, is provided for adjustably coupling the remaining opposing ends of the first and second links. The mating plug includes four sides and one hole disposed eccentrically therethrough and parallel to the sides. The remaining end of the second link includes a socket for mating with the plug. The plug can be mated in eight different rotational positions with respect to the socket. At each of the eight different rotational positions, the eccentric hole is disposed in a position which determines one of a predetermined number of available couplings between the first and second links.

Abstract: A separable connector module for live switching of shielded electrical power cable comprises a rod contact and a rod-shaped follower molded about a reinforcing pin fixed to one end of the rod contact. The follower is of thermoplastic ablative material consisting essentially of acetal resin loaded with melamine; the melamine constituting between one-fourth to about one-half the ablative material by weight.

Abstract: A thyristor-switched inductor circuit is connected across a portion of a power system at which good regulation is desired. The thyristor-switched circuit delivers a leading or lagging current to compensate for a load of varying reactance and provides proper regulation at the desired portion of the power system. The thyristor-switched circuit comprises two parallel circuit branches each comprising an inductor and a thyristor in series, the thyristors being oppositely poled. The thyristor-switched circuit is operated during both the normal and the transient overvoltage conditions of the power system. During normal conditions the thyristor-switched circuit is operated at a conduction angle of less than 180.degree. so that the forward and reverse currents, related to the thyristors, are not in an overlapped condition. Conversely, during transient overvoltage conditions the thyristor-switched circuit is operated at a conduction angle of greater than 180.degree.

Abstract: Clearance control means is provided for a gas turbine engine. In one embodiment relating to compressor blade clearance, means is provided for developing a first signal representative of the actual compressor casing temperature, a second signal representative of compressor inlet gas temperature, and a third signal representative of compressor speed. Schedule means is provided for receiving the gas temperature and compressor speed signals and developing a schedule output signal. The schedule output signal is representative of a reference casing temperature at which a predetermined compressor blade stabilized clearance is provided. Means is provided for comparing the actual compressor casing temperature signal and the reference casing temperature signal and developing a clearance control signal representative of the difference therebetween.

Abstract: Clearance determination is made between an edge of a translating member, e.g., a rotating blade member, and a relatively stationary second member, e.g., a shroud. In one form, an optical probe is provided for directing light from a light source to the edge and for collecting light scattered back from the edge. The probe includes first and second adjacent channels, optically separated by an opaque baffle. Probe output means and signal processing means are provided for developing a stored or displayed representation of the instantaneous clearance between each of a plurality of rotating blades and a stationary member, such as the turbine blade shroud. The probe may employ a continuous or intermittent light source. Synchronization techniques are provided for use with the intermittent light source wherein the light source is turned on only when needed to make the appropriate clearance determination. Other embodiments are disclosed.

Abstract: Clearance control between an outer air seal of a gas turbine engine and an internal, turbine section of the engine is controlled by selectively modulating a cooling air supply that is directed to selected portions of the air seal supporting structure to control its thermal growth. Impingement of the cooling air causes contraction of the seal structure, thereby lessening the clearance for the purpose of improving engine performance. The flow of cooling air is modulated in response to engine speed and engine altitude to maintain relatively low clearance during critical periods of engine operation.

Abstract: A continuous 360.degree. impingement baffle is attached directly to a shroud support structure such that the combination provides a low-leakage, high pressure plenum for supplying impingement airflow to the turbine rotor shroud for cooling purposes. After impingement, the air is at a low-pressure and is free to feed the conventional leakage paths with little loss of system efficiency.

Abstract: A plug including an axial shaft, a mating end of which is spring coupled to a mating portion of a sealing plug. The other end of the shaft includes an externally threaded portion and a flanged portion. The sealing plug also includes an externally threaded portion and a flanged portion. The spring normally mates the shaft and sealing plug together so that the members are rotationally engaged. When the spring is suitably compressed, the mating relationship is removed so that the members are rotationally disengaged. The plug is particularly useful in conveniently sealing double wall combustors such as those in gas turbine engines.

Abstract: A plurality of blocker door vanes are disposed in the bypass duct to selectively close off the bypass flow and increase the flow and pressure of the air flowing into the compressor. In this way, the compressor inlet pressure can be increased sufficiently to allow air starts without starter torque assist. The vanes may also be closed down during ground idle to reduce the thrust and increase the compressor bleed pressure and both the pressure and the temperature of the air to the combustor. Provision is made for the controlling of the blocker door vanes as a function of core speed.