Abstract: A method of enhancing alignment marks defined in a relatively thin layer on a wafer by etching the alignment marks into an underlying alignment mark transfer layer is described. The target area for the alignment marks is prepared by depositing material for the transfer layer. In alternative embodiments an oversized trench is formed in the target area prior to the deposition of the transfer layer. The alignment marks can fabricated in the layer(s) deposited by the existing process or alternatively, the original layers can be removed and replaced with a layer of material selected to have comparable etching properties (definition layer).

Abstract: A process for ion milling using photoresist as a mask is described. In a preferred embodiment the invention is used in the fabricating air-bearing features on sliders for use in magnetic storage devices. According to the invention the photoresist (liquid or dry) is applied, developed and removed as in the prior art which includes baking steps. The embodiment of the invention includes an additional baking step beyond whatever baking steps are used in the photolithography process. The additional baking step is preferably performed immediately prior to ion milling. The additional baking step according to the invention yields increased uniformity of the depth of the ion milling which is believed to result from reduction of volatile material such as water in the photoresist. When the invention is used as part of the manufacturing process for ion milling the air-bearing features on a slider, the features are more uniform which improves the overall quality and performance.

Abstract: An embodiment of the invention is a layered magnetic thin film structure that uses antiferromagnetically coupled (AFC) magnetic layers where the top layer structure consists of an upper magnetic layer that is weakly ferromagnetically coupled via a nonmagnetic or weakly magnetic exchange coupling layer (interlayer) to a ferromagnetic exchange enhancing layer that is in turn, AF coupled to the lower ferromagnetic layer of the AFC structure. Preferred materials for the weak coupling layer include alloys of cobalt such as CoRu, CoBRu and CoCr in which the Co content is below the point at which the material would be ferromagnetic. A second embodiment of the invention is a laminated, AF-coupled media structure. In this structure the lower AFC layer that makes up the lower laminate layer includes: the middle magnetic layer, the weak ferromagnetic coupling layer, and the exchange enhancing layer.

Abstract: A method for fabricating sliders (magnetic heads) with a recessed surface around a magnetic feature such as the active components of the write head on the air-bearing surface (ABS) is described. An embodiment of the method applies a positive photoresist to the exposed ABS surface, a magnetic field is applied, then liquid ferrofluid is applied on top of the photoresist. The pole pieces around the write gap will interact with the applied magnetic field so that the field gradient is highest around the write gap and the mobile ferrofluid will preferentially collect in the areas of the surface having the highest magnetic field gradient. The opaque magnetic particles in the ferrofluid form an optical ferrofluid mask over the photoresist around the write gap. The unmasked surface of the slider is milled which results in the recession of material around the write gap.

Abstract: A read head for a disk drive and a method of fabricating the read head with overlaid lead pads that contact the top surface of the sensor between the hardbias structures to define the electrically active region of the sensor are described. The invention deposits the GMR and lead layers before milling away the unwanted material. A photoresist mask with a hole defining the active area of the sensor is preferably patterned over a layer of DLC that is formed into a mask. A selected portion of the exposed lead material is then removed using the DLC as a mask defining the active region of the sensor. A photoresist mask pad is patterned to define the full sensor width. The excess sensor and lead material exposed around the mask is milled away. The layers for the hardbias structure are deposited.

Abstract: A disk drive including a slider with one or more sacrificial structures (extensions) that facilitate lapping to create the air-bearing surface (ABS) is described. The slider includes a magnetic transducer and has a remaining portion of a sacrificial extension protruding on an air-bearing surface, the remaining portion of the sacrificial extension is narrower than the air-bearing surface and aligned with the magnetic transducer. The sacrificial extension makes the surface of the slider which will be lapped non-planar. The sacrificial extension extends below the predetermined ABS plane. When the sliders are individually separated by DRIE, the shape of a mask including the sacrificial extension is projected down into and along the slider body. The mask and resulting slider includes a channel in the slider body that is aligned with the sacrificial extension and disposed on a surface of slider body that is parallel to and opposite from the air-bearing surface.

Abstract: Heads for perpendicular recording using a floating-trailing shield are described. The floating-trailing shield is separated from the main pole piece by a layer of non-magnetic material along its entire length and the air bearing surface of the floating-trailing shield is substantially larger than that of the main pole piece. The reluctance between the trailing shield and the underlayer in the recording medium is made so low that both are at the same magnetomotive force (or potential), so that no direct connection is needed between the floating-trailing shield and the yoke. When the head is used in a storage system with a magnetic recording medium with a soft underlayer, the floating-trailing shield is, in effect, magnetically shorted to the return pole piece during recording. In one embodiment the floating-trailing shield wraps around the sides of the main pole piece.

Abstract: An embodiment of the invention clamp assembly for a disk which includes a cavity for trapping the excess lubricant which migrates from the load bearing threads of the screws that hold the assembly in place. In a preferred embodiment a flexible structure, called a screw lubricant trap, is included between a clamp and hub. A recess for the screw lubricant trap is formed in one or both of the mating surfaces of the clamp and/or the hub. The screws are arranged in the interior of the screw lubricant trap, so that when the hub is spinning, the excess lubricant is forced into the cavity to keep the excess lubricant from migrating onto the disk. The screw lubricant trap is preferably made to be non-load bearing to avoid affecting the load on the screw. Alternatively, a groove can be machined in the clamp to serve as the lubricant trap.

Abstract: A method using a CMP resistant hardmask in a process of fabricating a pole piece for a magnetic head is described. A set of layers used as the mask for milling the pole piece preferably includes a CMP resistant hardmask of silicon dioxide, a resist hardmask, an upper hardmask and a photoresist mask respectively. A multi-step reactive-ion etching (RIE) process is preferably used to sequentially remove the excess materials in the layer stack to ultimately define the multilayer mask for the pole piece. The excess pole piece material is then milled away. The wafer is then refilled with a nonmagnetic material such as alumina. A CMP liftoff is used to remove the resist hardmask. The material for the CMP resistant hardmask is selected to have a high resistance to the CMP liftoff process in comparison to the refill material. The CMP resistant hardmask is preferably then removed by a RIE process.

Abstract: An antiferromagnetically coupled (AFC) magnetic recording medium with an AFC master layer comprising at least two magnetic layers with the top magnetic layer including copper is described. The slave layer is separated from the master layer structure by a nonmagnetic spacer layer selected to antiferromagnetically couple the layers. The master layer structure according to the invention includes a bottom and top layer of distinct ferromagnetic materials. Preferably, the top layer of the master layer is a cobalt alloy including from 1 to 5 at. % copper with an example being CoPt13Cr20B8Cu2. The AFC magnetic layer structure can be used with a variety of substrates including circumferentially textured glass and NiP/AlMg.

Abstract: A recording medium according to the invention has a magnetic recording layer with an L10 magnetic material deposited with a (111) preferred orientation and soft underlayer (SUL). One set of embodiments includes an intermediate layer (seed layer or underlayer) between the L10 media and SUL. The intermediate layer can be a close-packed surface structure (triangular lattice) to promote (111) orientation of the L10 media. For example, the intermediate layer can be a (111) oriented, face-centered-cubic (fcc) material such as platinum, palladium, iridium, rhodium, FePt, FePd, or FePdPt alloys; or the intermediate layer can be a (100) oriented hexagonal-close-packed (hcp) material such as ruthenium, rhenium, or osmium. Alternatively, the intermediate layer can be an amorphous material. The L10 recording layer of the invention can be deposited with a matrix material to form grain boundaries and provide magnetic isolation of the grains of L10 material.

Abstract: A method of fabricating a magnetic transducer is described which uses a trailing shield throat pad to set the trailing shield throat height. The trailing shield throat pad is used as a part of the structural form over which the material for the trailing shield is formed. The trailing shield throat pad is preferably made of a material which can selectively be removed from the gap layer with a selective etching process such as reactive-ion etching (RIE). The front edge of the trailing shield throat pad is used to define a peninsula on the trailing shield and thereby the throat of the trailing shield.

Abstract: An intelligent disk drive is described which includes means for prioritizing execution of command by maintaining an associated priority with each command in a pending command list and executing the highest priority commands first. The command structure according to the invention includes a field in which the host specifies the priority of the command. One embodiment uses a plurality of stacks which are used to sort the command according to priority. Another embodiment uses a list structure. In an alternative embodiment the drive has means for ensuring that designated data written to the disk is not subject to fragmentation. The disk drive embodiments described above can be implemented in an intelligent disk drive with distributed processing capability.

Abstract: A method is provided for fabricating a head for perpendicular recording with self-aligning side shields. The voids where the side shields will be formed are milled into the layer of material for the pole tip to achieve self-alignment. A mask is patterned with openings defining initial shape of the pole piece tip nearest the air-bearing surface including the width and the point at which the pole tip widens out. A film of soft magnetic material to form the side shields is deposited over the wafer. A chemical-mechanical-polishing process is preferably used to remove the mask and the material deposited on it. A new mask is patterned over the predetermined area for the final shape of the pole tip and the side shields. The excess side shield material and pole tip material outside of the mask is then removed.

Abstract: A disk drive is described having a capability of burnishing the sliders on demand by using a heater in the slider to thermally protrude the slider. Each slider includes a heating element with a sufficient thermal expansion stroke to bring the area of the slider containing the transducer into contact with the disk surface to burnish the slider. Preferably the heater is used to bring the slider into contact with the disk to burnish the lowest flying part of the slider body after the drive has been assembled, and remove most or all of the overcoat and recession, and exposing the transducers at the ABS. The burnish process is performed in situ in the drive and the drive is preferably hermetically sealed to reduce the risk of corrosion. The slider can be flown and magnetically tested prior to burnishing off the overcoat to avoid corroding the head before the drive is assembled.

Abstract: A process is described for fabricating sliders with reduced lapping damage to the hard-bias materials. The stack of layers for the magnetic sensor is deposited on a wafer and patterned into an initial shape. The hard-bias structures are fabricated at the side of the magnetic sensor as in the prior art. In each of the two described embodiments of the invention, the hard-bias material below the ABS is reduced or removed and replaced with a fill material such as alumina. A first embodiment reduces the hard-bias material below the ABS by forming an extended lapping gap along the ABS in both the sensor and hard-bias material. A second embodiment forms a photoresist mask over the sensor and the portion of the hard-bias/lead structures above the ABS and the exposed hard-bias/lead material below the ABS is thinned or completely removed by milling.

Abstract: A method of making and using thin film calibration features is described. To fabricate a calibration standard according to the invention raised features are first formed from an electrically conductive material with a selected atomic number. A conformal thin film layer is deposited over the exposed sidewalls of the raised features. The sidewall material is selected to have a different atomic number and is preferably an nonconductive such as silicon dioxide or alumina. After the nonconductive material deposition, a controlled directional RIE process is used to remove the insulator layer deposited on the top and bottom surface of the lines and trenches. The remaining voids between the sidewalls of the raised features are filled with a conductive material. The wafer is then planarized with chemical mechanical planarization (CMP) to expose the nonconductive sidewall material on the surface. The nonconductive sidewall material will be fine lines embedded in conductive material.

Abstract: A thin film disk for use in magnetic recording with an underlayer structure that includes a layer of CrMoZr, CrMoNb or CrMoMn is described. The preferred embodiment includes a circumferentially textured glass substrate, a pre-seed layer, a B2 seed layer, an underlayer structure and a magnetic layer stack with a plurality of layers. The preferred underlayer structure has a first underlayer of CrTi followed by a second underlayer of CrMoZr. The preferred B2 seed layer material is RuAl. The preferred pre-seed layer is CrTiAl. The preferred magnetic layer stack is CoCr/CoPtCrB/CoPtCrBCu. The preferred embodiment is useful for longitudinal magnetic recording. The in-plane crystallographic orientation, the Mrt orientation ratio and the media SNR are improved by the inclusion of the CrMoZr, CrMoNb or CrMoMn according to the invention.

Abstract: A method of physical vapor deposition (PVD) is disclosed in which xenon is used as the operating gas in the vacuum chamber in the deposition of an adhesion layer, preferably silicon, which allows the adhesion layer to be ultra-thin with improved durability over prior art films. The use of argon as is typical in the prior art results in argon atoms being incorporated into the ultra-thin silicon film with deleterious results. In films that are only several angstroms thick, the contamination of the film with argon or other elements can yield a film with reduced adhesion performance and in some cases noble atoms such as argon can escape the film leaving voids or pinholes. The use of the larger and heavier xenon atoms in the vacuum chamber produces a substantially purer film with reduced risk of voids and pinholes.

Abstract: A method is described for thin film processing using a selected CMP slurry with a silicon dioxide stop layer. The slurry includes an abrasive, preferably alumina, a corrosion inhibitor, preferably benzotriazole (BTA), and an oxidizer preferably hydrogen peroxide. The method is particularly useful for fabricating thin film heads where alumina is used as the dielectric. The method can be used to planarize metal structures surrounded by alumina in magnetic heads. The alumina refill is deposited to the final target height which is slightly below the height of the metal. A thin silicon dioxide stop layer is deposited over the alumina. The CMP is executed using the selected slurry to planarize the wafer down to the stop layer. Preferably only a negligible amount of the stop layer remains and the height of the metal structure is essentially the same as the deposited height of the refilled alumina.