Abstract: A magnetic head including a GMR read head structure in which the outer end portions of the free magnetic layer are magnetically stabilized. The stabilization is achieved by the fabrication of thin film layers on top of the outer end portions that have an anti-parallel coupled magnetic field structure. A seed layer having a BCC crystal structure is deposited before a first magnetic field layer to increase coercivity of the anti-parallel coupled structure. The thickness of the layers is selected to produce a high coercivity structure having a net magnetization in the same direction as the magnetic field of the free magnetic layer. The anti-parallel coupled structure preferably includes a CoFeCr seed layer, a CoPtCr first magnetic layer, an Ru nonmagnetic layer and a CoPtCr second magnetic layer. An enhanced structure includes two CoFe layers formed below and above the Ru layer.

Abstract: A magnetic head having a helical induction coil. The helical coil is fabricated around a magnetic pole yoke in a series of process steps that include a reactive ion etch (RIE) process step which is utilized to simultaneously form vertical interconnect vias and upper helical coil member trenches. Thereafter, in a single fabrication step, such as by electroplating, the vertical interconnect lines and the upper helical coil traces are created in a single fabrication step, such that they are integrally formed. The vertical interconnect lines provide an electrical connection between outer ends of previously formed lower helical coil traces and outer ends of the integrally formed upper helical coil traces, such that a helical coil is fabricated. In the preferred embodiment, the helical coil is composed of copper.

Abstract: The trenchless water pipe replacement device includes a cable pulling device, a pipe splitter, a length of cable and a cable end piece. The cable is fished through a pipe that is to be replaced, and a length of replacement pipe is attached to the end piece. The pipe splitter is disposed at the front end of the pipe and the cable pulling device is disposed behind the pipe splitter. When the cable pulling device is activated, the end piece makes contact with the rear end of the pipe and sufficient pulling force is applied to the cable to dislodge the pipe and pull it onto the pipe splitter, which splits the pipe as it is pulled from the ground. The replacement pipe is pulled behind the end piece, such that when the end piece is entirely pulled through the ground, the replacement pipe is disposed in its place.

Abstract: The basic features of the invention include a pipe parting mole, a length of cable that is engagable to the mole, a cable pulling device and a cable pulling device engagement means that provides a mounting structure for the cable pulling device. The cable pulling device engagement means generally includes a reaction plate and a structure for removably engaging the cable pulling device therewithin. A cable pulling frame may be advantageously used to facilitate the removal of the cable from a relatively small hole that is created at the pulling end of the pipe.

Abstract: A method for determining a characteristic of a magnetic head during its fabrication process on the surface of a wafer substrate. The method involves the fabrication of a test magnetic pole artifact in a field area of the substrate surface adjacent to the actual magnetic pole that is being fabricated. A test pole structure is fabricated simultaneously with, and utilizing the same fabrication conditions and parameters as, the actual pole such that the test pole is nearly identical to the actual pole. During a field etch step undertaken in the fabrication of the actual pole, portions of the test pole structure are removed, leaving a test pole artifact on the wafer surface. The test pole artifact can thus be easily measured as an accurate indication of characteristics of the actual magnetic pole that are difficult to measure directly, thereby saving time and expense in the magnetic head fabrication process.

Abstract: The method for controlling the depth of polishing during a CMP process involves the deposition of a polishing stop layer at an appropriate point in the device fabrication process. The stop layer is comprised of a substance that is substantially more resistant to polishing with a particular polishing slurry that is utilized in the CMP process than a polishable material layer. Preferred stop layer materials of the present invention are tantalum and diamond-like carbon (DLC), and the polishable layer may consist of alumina. In one embodiment of the present invention the stop layer is deposited directly onto the top surface of components to be protected during the CMP process. A polishable layer is thereafter deposited upon the stop layer, and the CMP polishing step removes the polishable material layer down to the portions of the stop layer that are deposited upon the top surfaces of the components. The stop layer is thereafter removed from the top surface of the components.

Abstract: In an essentially flat contour linear tape recording head, a nominal tape wrap angle exists at which reading signals from the magnetic tape ceases and/or commences. This nominal tape wrap angle can be easily determined by monitoring a prerecorded signal, such as the servo track signal, while the tape wrap angle is adjusted. When the signal ceases (or starts, depending upon the direction of adjustment) an initial position of the tape movement control device relative to the tape wrap angle is identified. At this initial position it is known that the tape wrap angle is at its nominal value, such as approximately 0.1°. Thereafter, the tape movement control device can be knowingly adjusted with a calibrated indicator to accurately and quickly achieve a desired final tape wrap angles.

Abstract: In the tape head polishing method of the present invention the tape head is moved orthogonally to the polishing medium (such as diamond polishing tape) direction of motion during polishing. The polishing medium motion is synchronized with the tape head motion, such that the polishing medium is held stationary when the tape head motion is stationary, and the polishing medium is moved when the tape head motion is approximately at a maximum velocity. The tape head velocity VH and the polishing medium velocity VT during the tape motion are generally related by the equation VT≦VH Tan &phgr;, where Tan &phgr;=W/L, where W is the width of an insulation layer fabricated between a magnetic shield and a tape head read sensor element, and L is the length of a read sensor element.

Abstract: Following the deposition of an insulation layer, a patterned P2 pole tip seed layer is deposited. Significantly, the pole tip seed layer is not deposited beneath the induction coil area of the magnetic head. A dielectric layer is next deposited and a patterned RIE etching mask that includes both a P2 pole tip trench opening and an induction coil trench opening is fabricated upon the dielectric layer. Thereafter, in a single RIE etching step, the P2 pole tip trench is etched through the dielectric material down to the seed layer, and the induction coil trench is etched through the dielectric material down to the insulation layer. The P2 pole tip is first electroplated up into its trench, an induction coil seed layer is next deposited, and the induction coil is then electroplated up into the induction coil trench.

Abstract: The present invention includes a two-step etching process for notching the P1 pole of the write head element of a magnetic head. In a first step, the preferred embodiment utilizes a combination of C2F6 and argon gases (designated as C2F6/Ar) as the etchant gas to preferentially etch portions of the alumna write gap layer. Thereafter, in the second step, argon is used as the etchant gas to preferentially etch the P1 pole material. The C2F6/Ar etchant gas preferably includes C2F6 gas in a concentration range of from 50% to 90%, with a preferred concentration range being from 70% to 80%. The etching of the alumna write gap layer is preferably conducted with a first echant ion beam angle of from 5° to 30°, and a second etchant ion beam angle of from 65° to 85°.

Abstract: A magnetic head for a hard disk drive. The magnetic poles of the head are formed with a NiFe alloy having a graduated composition in which a higher Fe concentration is fabricated proximate the write gap layer between the magnetic poles. Each magnetic pole is fabricated in a single electroplating step in which the duty cycle of the electroplating current is altered during the electroplating operation. Where the duty cycle is greatest the Fe ion concentration is likewise greatest.

Abstract: A magnetic head includes a GMR read head that is protected from electrostatic discharge (ESD) on a slider by a silicon germanium (SiGe) integrated circuit device. In a preferred embodiment the SiGe circuit device includes one or more silicon germanium heterojunction bipolar transistors (SiGe HBT) or silicon germanium carbon heterojunction bipolar transistors (SiGeC HBT) that is electrically connected across the electrical leads of the GMR read head. Particular electrical connection configurations with the SiGe circuit devices include diodic modes, npn modes, series cascade modes and two stage ESD network configurations. The silicon chip may be sandwiched between the slider body and the read/write head or the read/write head may be sandwiched between the slider body and the silicon chip.

Abstract: A computer hard disk drive has a drive controller that monitors the condition of the head-disk interface within the drive. The drive normally operates under ambient or relatively low internal pressure. However, when the drive is in imminent risk for a head-disk interface failure, the drive is pressurized to allow the air bearing surfaces of the heads to achieve a greater flying height above the surfaces of their respective disks, thereby delaying the onset of a catastrophic head-disk interface failure. In addition, the spindle rotation rate and/or the slider head access rate are decreased to avoid hastening the imminent failure. Measurements of the condition and stability of the head-disk interface inside the drives are made by monitoring data error rates, head flying height, and other performance variables.

Abstract: The hard disk drive of the present invention includes a magnetic head wherein the read head portions have gap insulation layers between the magnetic shields. The gap insulation layers are made up of multilayered laminations of an oxide or nitride of a metal such as aluminum, silicon, chromium, and tantalum. A preferred embodiment of the present invention includes laminated G1 and G2 gap insulation layers having 5-10 laminations, and having a total thickness of approximately 50 Å to 500 Å.

Abstract: A wafer boat and boat handle are designed for automatic interlocking engagement and release upon manipulation by a user. The boat includes a side rail with a lip for engagement within a slot formed in the handle, and a handle cam activating contact surface for contacting a gripping block member of the handle. The handle includes at least one boat holding block with a boat lip holding slot therewithin. The handle also includes at least one boat gripping block that is rotatably engaged with the holding block, and which includes a frontwardly projecting rail gripping flange. When the boat lip is brought into the holding block slot, the gripping block rotates and the flange is brought over the top of the rail. The boat rail is thereby held between the slot and the flange of the handle, such that the boat may be lifted and moved.

Abstract: The magnetic tape recording head of the present invention is formed with magnetic poles that are comprised of a laminated NiFeN/FeN structure. The method for fabricating the magnetic poles utilizes an additive photolithographic technique including a bilayer liftoff resist. In this fabrication method magnetic pole trenches are formed in the bilayer liftoff resist such that an undercut exists in the liftoff layer. Thereafter, the laminated NiFeN/FeN structure is sputter deposited into the trench, followed by the wet chemical removal of the bilayer resist.

Abstract: An artwork is made on a surface of a matrix or plate with acrylic paint and then allowing the paint to dry. A layer of a backing material adhesive, such as an acrylic gel, is next applied to the acrylic layer and a backing material (such as paper or cloth) is placed upon the gel, and the wet gel is then allowed to dry. The dry artwork is then removed from the matrix. The invention allows the inclusion within a single image of other media (wet or dry), such as paper, fabric, dry acrylic elements, watercolor, waterbase crayons and pencils, felt pens, waterbase inks, water mixable oil paints, oil pastels and oil paint sticks because of the bonding abilities of acrylics.

Abstract: A tree harvester including an automated tree sensing and shaking control system. The control system includes a tree sensing device, such as an ultrasonic sensor that is mounted upon the harvester. Predetermined tree distance values and other shaker head control parameters are input into a programmable logic control (PLC) device of the control system. When the harvester is located next to a tree, the operator initiates an automated tree shaking cycle in which the tree sensor provides distance values to the tree as input signals to the controller. The shaker head automatically moves outward towards the tree until the inputted distance values to the tree are equal to or less than the predetermined tree distance values. The control system then causes the shaker head to clamp the tree, to shake the tree, to unclamp the tree and to move the shaker head back to the harvester.

Abstract: In the present method for manufacturing a magnetic write head a focused ion beam (FIB) tool is utilized to mill the side edges of a P2 pole, in order to provide a narrowed track width. Prior to milling, a thin film layer of material is deposited upon the P2 pole tip. The milling boxes of the FIB tool are properly aligned upon the layer with reference to the location of the P2 pole tip. Milling of the lateral edges of the P2 pole tip is then conducted to the appropriate depth, and the layer of material is removed. The resulting P2 pole tip has sharp lateral edges, rather than the rounded edges that are produced in prior art FIB processing methods that do not utilize the thin film layer. In a preferred implementation, the FIB tool is utilized first to deposit the thin film layer and thereafter to perform the milling operation.

Abstract: A mechanical linkage, including a worm gear and a worm gear support bracket, for joining a drive motor to a helical gear; it is particularly adapted for controlling a tape drive head. The worm gear head is threadably engaged with the helical gear. The shaft of the worm gear is engaged with the motor and is sufficiently flexible to operably correct misalignments between the worm gear shaft and the motor shaft. The support bracket includes a flat leaf spring which provides lateral spring force against the worm gear shaft to maintain a driving engagement between the worm gear and the helical gear, while the leaf spring is stiff in the in-plane directions of movement. The support bracket also includes a bushing, such as a C-shaped bushing or a cylindrical bushing, which provides support for the worm gear shaft against the helical gear.