Abstract: A method for constructing a magnetoresistive sensor that avoids shadowing effects of a mask structure during sensor definition. The method includes the use of an antireflective coating (ARC) and a photosensitive mask deposited there over. The photosensitive mask is formed to cover a desired sensor area, leaving non-sensor areas exposed. A reactive ion etch is performed to transfer the pattern of the photosensitive mask onto the underlying ARC layer. The reactive ion etch (RIE) is performed with a relatively high amount of platen power. The higher platen power increases ion bombardment of the wafer, thereby increasing the physical (ie mechanical) component of material removal relative to the chemical component. This increase in the physical component of material removal result in an increased rate of removal of the photosensitive mask material relative to the ion mill resistant mask.

Abstract: To remove unwanted electrostatic charge from a substrate or substrate clamping mechanism in a plasma processing chamber following the plasma processing of the substrate, the process of shutting down the RF power supply is altered. Specifically, the present invention is a stepped RF power shut down sequence in which the RF power is lowered in a first step from full power to approximately 5 to 10 watts for a short period of time, such as approximately 1 second, and thereafter the RF power is turned off. As a result of this RF power shut down sequence, with its intermediate step, the plasma during the intermediate step acts to neutralize or discharge the electrostatic charge that has built up upon the wafer and/or clamping mechanism during full power operation. When the electrostatic charge has been removed, the wafer sticking problem is resolved.

Abstract: An improved damascene method of forming a write coil of a magnetic head includes forming a hard mask layer over an insulator layer; forming a photoresist layer over the hard mask layer; performing an image patterning process to produce a write coil pattern in the photoresist layer; etching to remove portions of the hard mask layer in accordance with the write coil pattern; etching to remove portions of the insulator layer in accordance with the write coil pattern; etching to remove the remaining portion of the etched hard mask layer; electroplating a material comprising copper (Cu) within the etched portion of the insulator material; and performing a chemical-mechanical polishing (CMP) process over the resulting structure. By removing the remainder of the hard mask material before the CMP, the quality of the CMP is improved.

Abstract: A cathode current control system employing a current thief for use in electroplating a wafer is set forth. The current thief comprises a plurality of conductive segments disposed to substantially surround a peripheral region of the wafer. A first plurality of resistance devices are used, each associated with a respective one of the plurality of conductive segments. The resistance devices are used to regulate current through the respective conductive finger during electroplating of the wafer. Various constructions are used for the current thief and further conductive elements, such as fingers, may also be employed in the system. As with the conductive segments, current through the fingers may also be individually controlled. In accordance with one embodiment of the overall system, selection of the resistance of each respective resistance devices is automatically controlled in accordance with predetermined programming.

Abstract: A cathode current control system employing a current thief for use in electroplating a wafer is set forth. The current thief comprises a plurality of conductive segments disposed to substantially surround a peripheral region of the wafer. A first plurality of resistance devices are used, each associated with a respective one of the plurality of conductive segments. The resistance devices are used to regulate current through the respective conductive finger during electroplating of the wafer. Various constructions are used for the current thief and further conductive elements, such as fingers, may also be employed in the system. As with the conductive segments, current through the fingers may also be individually controlled. In accordance with one embodiment of the overall system, selection of the resistance of each respective resistance devices is automatically controlled in accordance with predetermined programming.

Abstract: A cathode current control system employing a current thief for use in electroplating a wafer is set forth. The current thief comprises a plurality of conductive segments disposed to substantially surround a peripheral region of the wafer. A first plurality of resistance devices are used, each associated with a respective one of the plurality of conductive segments. The resistance devices are used to regulate current through the respective conductive finger during electroplating of the wafer. Various constructions are used for the current thief and further conductive elements, such as fingers, may also be employed in the system. As with the conductive segments, current through the fingers may also be individually controlled. In accordance with one embodiment of the overall system, selection of the resistance of each respective resistance devices is automatically controlled in accordance with predetermined programming.

Abstract: A system and method are disclosed for equalizing a read signal from a data storage media is disclosed. An analog output signal is equalized by reading the data storage media using an analog equalization filter. The analog output of the analog equalization filter is converted to a raw digital output signal. The raw digital output signal is processed to detect and correct an error in the raw digital output signal. The error is detected and an adjustment is made to the boost of the analog equalization filter according to the error detected.

Abstract: An apparatus for rotary cathode electroplating having a head assembly, a substrate/thief assembly having a thieving ring which includes a number of individually chargeable segments, and a secondary induction assembly including a secondary core and a secondary winding. A motor drives the substrate/thief assembly to rotate relative to the head assembly. A controller directs electrical charge to each of the individually chargeable segments of the thieving ring. An electrical storage device stores electrical energy which is to be supplied to the controller. A charging apparatus induces a magnetic flux which induces an alternating current in the secondary winding of the secondary induction assembly. A converter converts the induced alternating current to direct current, which is then stored on the electrical storage device.

Abstract: A magnetic induction device having at least one secondary induction assembly including a secondary winding is mounted on a rotary element. A magnetic flux is induced the secondary induction assembly, causing an induced secondary alternating current in the secondary winding of the secondary induction assembly. The secondary alternating current is converting to direct current and is stored in an electrical storage device.

Abstract: A cathode current control system employing a current thief for use in electroplating a wafer is set forth. The current thief comprises a plurality of conductive segments disposed to substantially surround a peripheral region of the wafer. A first plurality of resistance devices are used, each associated with a respective one of the plurality of conductive segments. The resistance devices are used to regulate current through the respective conductive finger during electroplating of the wafer. Various constructions are used for the current thief and further conductive elements, such as fingers, may also be employed in the system. As with the conductive segments, current through the fingers may also be individually controlled. In accordance with one embodiment of the overall system, selection of the resistance of each respective resistance devices is automatically controlled in accordance with predetermined programming.

Abstract: A cathode current control system employing a current thief for use in electroplating a wafer is set forth. The current thief comprises a plurality of conductive segments disposed to substantially surround a peripheral region of the wafer. A first plurality of resistance devices are used, each associated with a respective one of the plurality of conductive segments. The resistance devices are used to regulate current through the respective conductive finger during electroplating of the wafer. Various constructions are used for the current thief and further conductive elements, such as fingers, may also be employed in the system. As with the conductive segments, current through the fingers may also be individually controlled. In accordance with one embodiment of the overall system, selection of the resistance of each respective resistance devices is automatically controlled in accordance with predetermined programming.

Abstract: The method and apparatus for supplying power to a rotary element by magnetic induction. A magnetic induction device having at least one secondary induction assembly including a secondary winding is mounted on the rotary element. A magnetic flux is induced the secondary induction assembly, causing an induced alternating current in the secondary winding of the secondary induction assembly. The secondary alternating current is converting to direct current and is stored in an electrical storage device. A rotary cathode plater is disclosed as a particular application of the apparatus by which power is transferred to a storage battery or high capacity capacitor, without the use of wires.

Abstract: Apparatus and methods are disclosed for adaptively optimizing an ER filter in a readback system of a storage device, such as a disk drive. A sample value is read from the storage device and an error measure is calculated between the sample value and an ideal value. Pole parameters and zeros of the ER filter are modified to minimize the ER filter. The apparatus and methods disclosed can function with customer data to adaptively optimize the ER filter in real time during normal operation of the storage device. Furthermore, temperature compensation circuits are disclosed to compensate for temperature dependencies in the ER filter.

Abstract: Analog-to-digital (ADC) output bits are partitioned in a way that simplifies the gain error calculations. Simplification of the gain error calculations allows a reduction in the complexity of the circuits needed to implement automatic gain control (AGC).

Abstract: A servo gate method and apparatus to allow switching between a servo mode and a data mode in the read channel of a disk drive. The present invention uses a servo gate signal to select components and parameters in the read channel of a disk drive. The servo gate signal, when enabled, preloads appropriate registers with new values and preloads the programmable filter with new values. The servo gate signal is not limited to preloading the above values, but may be used to control many characteristics of a disk drive read channel.

Abstract: A dual mode charge pump for an AGC circuit is described. The charge pump of the present invention provides normal and accelerated rates of charge and discharge of a capacitor used to control the gain of an AGC amplifier. Current sources for providing accelerated charge and discharge rates are deselected when not needed. Since these current sources consume substantial amounts of power, deselecting them increases efficiency and reduces unnecessary power consumption. The current sources may be deselected internally or may be switched off by a switches in series with the current sources. The present invention also may be used to provide a self-timing function. The self-timing function allows the AGC to acquire the correct gain in an optimum time after initiation by an external control signal.