Abstract: A multi-station processing chamber in which incompatible processes are performed includes multiple pedestals positioned in wells with annular gaps around the pedestals. Showerheads located above the pedestals flow reactive gases over substrates located on the pedestals. The reactive gases are drawn through the annular gaps by a pressure gradient. The reactive gases are then pumped out of the wells through an exhaust port. The narrow annular gap permits little recirculation of the reactive gases one they are drawn into the wells. Moreover, the showerheads are flush with ceiling of the chamber and the wells contain smooth contours to minimize dead space in the chamber thereby reducing residence time of the reactive gases. An indexing plate is used to lift the substrates off the pedestals and to accurately position the substrates at the next processing station.

Abstract: An optical scanning device for raster scanning applications based on galvanometric scanner technology incorporates a nonlinear biasing element, such as a nonlinear magnetic or mechanical spring to assist in the acceleration and deceleration of the motor shaft at the turn around points of the sawtooth motion. The galvanometric scanning device includes a moving magnet motor using more than four poles, e.g., eight poles. The moving magnet motor has a plurality of laminations each having a number of teeth, e.g., eight, extending inward toward the rotor and having coils mounted thereon. In one embodiment, coils are mounted on every other tooth. The motor is driven with a fourth order polynomial sawtooth command signal to reduce resonances caused by high acceleration and deceleration. In addition, the motor may be driven by pulse width modulation to reduce power dissipation.

Abstract: A lower metal plate having a strip-like opening is used in a bond pad structure having metalplugs coupling the lower metal plate to an upper metal plate. A volume of relatively rigid material filling a volume above the strip-like opening transfers stress from the upper metal plate, through the strip-like opening, and to a foundation layer upon which the lower metal plate is disposed. The bond pad structure can be fabricated using the same semiconductor processing steps used to fabricate amorphous silicon antifuse structures having metal plugs.

Abstract: A monitoring device is used to monitor the performance of a burnishing apparatus that uses a burnishing tape. The monitoring device monitors the contact between the burnishing tape and the disk. The monitoring device may include an acoustic emission sensor, e.g., a piezo-electric transducer, that is mounted on the elements that press the burnishing tape into contact with the disk. Elastic waves that are produced by the contact between the burnishing tape and the disk propagate through the pressure applying element, received by the sensor and are converted into electric signals. The electric signals from the sensor are converted into amplitude signals in the time domain and/or signals in the frequency domain. Alternatively, the monitoring device may measure the elastic waves propagating through the disk, the tension on the burnishing tape, and/or the frictional force between the burnishing tape and the disk.

Abstract: The precharge operation of a DRAM array in a non-multiplexed address interface is controlled so that the DRAM is precharged only if there is a change in the word line address. By precharging the DRAM only when a new word line is asserted, a significant power savings may be obtained. An activity monitor compares each new word line address with the previous word line address. If the activity monitor indicates that a new word line is asserted, a timing control circuit will precharge the DRAM, including equalizing the bit lines. If the activity monitor indicates that the word line is not changed, the timing control circuit does not precharge the DRAM. The timing control circuit includes a dummy precharge circuit and initiates a dummy precharge cycle in the beginning of each new cycle for timing purposes. The timing control circuit initiates the active cycle after the dummy precharge cycle regardless of whether a new word line is asserted or not.

Abstract: A burnishing tape apparatus includes pads that press the burnishing tape against the surfaces of the disk to be burnished. The pads are mounted on pad holders that are biased to press the pads against both sides of the disk. Tape guides are used to apply tension to the burnishing pad when the pads are moved away from the disk. When the pads are away from the disk tape guides hold the burnishing tape away from the pads so that the burnishing tape may be indexed without damaging or dislodging the pads. As the pads are moved into contact with the disk, the tape guides release the tension on the burnishing tape while the centering guides ensure that the burnishing tape is centered on the pads. By releasing tension on the burnishing tape, the pads are permitted to press the approximate center of the burnishing tape against the surfaces of the disk without deforming in an uncontrolled manner.

Abstract: A processing chamber with a showerhead and a chuck is cleaned using an injection of a gaseous cleaning agent through an aperture in the chuck into the processing chamber. Because the aperture is located directly under the showerhead, a portion of the gaseous cleaning agent passes through the face plate of the showerhead so that the inside of the showerhead may be cleaned as well. By applying a radio frequency power supply between the chuck and the showerhead, for example, by a coil located between the chuck and showerhead or applying the power directly to the chuck and the showerhead, the gaseous cleaning agent forms a plasma. Thus, the portion of the gaseous cleaning agent that passes through the face plate and into the showerhead is a plasma. The plasma is pumped out of the chamber through a pumping port so that the plasma continuously flows through the processing chamber.

Abstract: A level flying burnishing head includes a plurality of burnishing pads, e.g., thirteen, that are symmetrically arranged about orthogonal axes on the bottom surface of the burnishing head. The burnishing pads may have a polygonal geometry having at least four sides. The corners between the sides of the burnishing pads may be rounded. The separation between the burnishing head is configured to fly substantially parallel to the surface of the disk that it is burnishing. The burnishing head may have no taper on the leading edge to achieve the level flying condition.

Abstract: A positioning system used, by way of example, for lithography, uses the position of the wafer stage as the trajectory command for the reticle fine stage control circuit. The reticle fine stage position is combined with the position of the wafer stage to generate a synchronous error. The reticle fine stage control circuit uses a Jacobian differential transformation to convert the synchronous error into an positional error for the center of gravity of the reticle fine stage. Thus, any inaccuracies due to measurement errors caused by rotation of reticle fine stage are avoided. A controller filter circuit uses the positional error for the center of gravity to calculate the force on the center of gravity that will minimize the synchronous error. The controller filter circuit includes saturation limited integration behavior that minimizes the settling time. A feedforward loop also generates a feedforward force, which reduces settling time, and is combined with the force signal from the controller filter.

Abstract: An equipment loading plank that is detachably mounted on a machine tool table and used for easy and safe installation and removal of equipment on and off the machine tool work tables. The equipment loading plank includes a flat rectangular shaped body with an upper loading surface and a lower seating surface and a leg downwardly extending at an angle from one end of said loading plank. The leg is inserted into a T-slot in the machine tool table to detachably mount the loading plank to the machine tool table. The leg has a front face and a lower face that converge such that the leg can be wedged into the T-slot when the loading plank is seated on the machine tool table parallel to the upper surface of the machine tool table. The leg ends in a foot that prevents the leg from slipping from the T-slot whenever loads are placed on the loading plank.

Abstract: A glide head using a slider with an outside active rail is described. In one embodiment, the trailing end of the outside rail extends beyond the trailing end of the inside rail. Thus, during use, the trailing end of the outside rail is closer to the surface of the magnetic disk because of the slope of the glide head's flight. Accordingly, the outside rail is the active rail. The inside rail may be wider than the outside rail to compensate for additional lift created by the greater length of the outside rail. In an alternative embodiment, the trailing end of the outside rail extends beyond the trailing end of the inside rail and there are notches located in the side edges of the rails. The notches do not extend to the forward tapered ends of the rails nor to the trailing ends of the rails. The notches provide additional stability during the slider's flight and decrease the air bearing area of the rails as needed for fly height requirements.

Abstract: A glide head with at least one rail includes a tapered trailing end on the at least one rail. The glide head flies with a pitch angle over the surface of the disk, thus, by tapering the trailing ends of the rails of the slider, the lowest flying point of the glide head is the junction of the air bearing surface of the rails and the trailing end taper. Because the junction of the air bearing surface and the tapered trailing end is the closest point on the glide head to the surface of the disk, the point of contact on the glide head is moved forward from the trailing end of the glide head. The tapered trailing end advantageously increases the amount of material surrounding the lowest flying point of the glide head relative to conventional glide heads. Consequently, the glide head with the tapered trailing end wears slower than conventional glide heads, and thus has an increased life. Further, the glide head with a tapered trailing end flies at a lower fly height than conventional glide heads.

Abstract: A highly linear, low-distortion H-bridge amplifier is described. The amplifier includes four interconnected power transistors connected to an inductive load. Each transistor has a precision voltage clamp connected between the source and drain to suppress ringing oscillations. Two or more of the transistors also include high-speed transient-voltage suppressers connected in parallel with their respective voltage clamps. These transient-voltage suppressers do not have the clamping accuracy of the voltage clamps, but respond much more quickly to suppress noise spikes. The amplifier therefore takes advantage of both the fast response time of the transient-voltage suppressers and the precise voltage-clamping characteristics of the voltage clamps.

Abstract: A floating point arithmetic logic unit includes two rounding units that select between an incremented, unincremented, and complemented result from a carry propagate adder. A fast rounding unit selects a result as an approximation based on the equality or inequality of the exponents of the operands, the relative sizes of the mantissas and the presence of a guard bit. The result selected by the fast rounding unit is received by a leading zero count unit, which counts the leading zeros of the result. A second slower rounding unit meanwhile makes a selection between the incremented, unincremented, and complemented results based on the rounding mode, the sign of the result and whether the result is exact. The result is inexact when both the most significant bit and the guard bit are equal to one. While the slower rounding unit may take longer to determine the appropriate selection, the result selected is the most accurate.

Abstract: A floating point unit includes a rounding unit that rounds the two least significant bits of a sum. After a sum of the two mantissas is generated the at least one least significant bit is separated from the sum. When addition is performed, two least significant bits are separated from the sum. A half add unit may be used to generate the sum along with a set of carry data, and thus at least one least significant bit of the carry data is also separated. A rounding unit receives the separated at least one least significant bit of the sum and carry data and produces a carry in bit as well as rounded at least one least significant bit. The sum and carry data are then summed in a later stage of the floating point unit to form both a unincremented sum and an incremented sum, which are stored in a multiplexer. The carry in bit is used to select one of the unincremented sum and incremented sum.

Abstract: A duct joining system for providing an air-tight seal and mechanical connection for ducts and fittings is disclosed. The duct joining system includes a flexible gasket affixed to a male end of a duct or fitting. The flexible gasket is affixed at an angle relative to normal of the male end of the duct. The female end of the other duct includes a raised bead in which the flexible gasket is seated when the ducts are properly joined. The angled flexible gasket seated in the raised bead forms an air-tight seal as well as fastens or locks the male end to the female end. Alternatively, when a flexible duct is used, a band clamp with a raised bead is clamped over the female end of the flexible duct and over the male end of a fitting to provide an air tight seal and fastened connection.

Abstract: A channel region is formed in a device after the source and drain regions are formed by implanting ions into the channel region with a tilt angle using multiple rotations. A rapid thermal annealing step is performed to activate the channel dopant. Because the source and drain regions are already formed, a relatively low temperature, e.g., 990 to 1010 degrees Celsius, and short, e.g., 1 to 5 seconds, rapid thermal annealing step may be performed to activate the channel region. Thus, the dopant concentration in the channel region may be well localized and accurately controlled.

Abstract: A programmable device, such as a field programmable gate array, includes at least one signature bit that is used to indicate whether the programmable device has fewer than all the logic blocks accessible to the user. The signature bit may be programmed after the manufacture of the programmable device or may be hard wired during the manufacture of the device. The programming unit recognizes the configuration of the signature bit and restricts access to particular logic blocks based on the configuration. Thus, a large programmable unit may become a smaller “virtual” programmable device by altering the configuration of the signature bit, which is recognized by the programming unit. Consequently, the manufacturer may test market programmable devices of differing sizes to determine demand without incurring the costs associated with producing a completely new product line.

Abstract: A temperature sensor corrects the parabolic curvature error in the output signal without attempting to linearize the reference voltage itself. A temperature sensor produces a temperature output signal that is a function of the ratio of a temperature dependent voltage to a reference voltage. The temperature sensor uses a nonlinear reference voltage, e.g., the reference voltage conforms to a curve with an approximately hyperbolic shape over a temperature range, so that the ratio of the temperature dependent voltage to the hyperbolic reference voltage will be linear. The hyperbolic reference voltage is generated by summing a reference voltage with an appropriate temperature dependent voltage. The “gain” or slope of the ratio is altered by adjusting a scaling factor. Finally, the offset of the ratio is adjusted so that the temperature sensor produces the appropriate output signal at ambient temperature.

Abstract: A burnishing head for burnishing the surface of magnetic or magneto-optical memory disks is described. The burnishing head comprises a plurality of curved burnishing pads symmetrically arranged on the bottom surface of the head. In one embodiment, there are thirteen circular burnishing pads symmetrically arranged on the bottom surface of a square burnishing pad in such a way that there is no dedicated leading edge of the burnishing head. The area between the curved burnishing pads is wide enough to allow the free flow of air to help the escape of debris created during burnishing. The burnishing head has no tapered leading edge. The burnishing pad flies parallel to the surface of the disk in a level manner, such that all burnishing pads are simultaneously used.