Patent application number | Description | Published |
20080204933 | Granular perpendicular magnetic recording media with multi-interlayer structure - A perpendicular magnetic recording medium comprises a layer stack formed over a surface of a non-magnetic substrate, and comprising, in overlying sequence from the surface: a magnetically soft underlayer; an interlayer structure for crystallographically orienting a layer of a perpendicular magnetic recording material formed thereon; and at least one crystallographically oriented, magnetically hard, perpendicular magnetic recording layer on the interlayer structure; wherein the interlayer structure is a triple-layer stacked structure comprising: a first interlayer of a first non-magnetic material proximal the magnetically soft underlayer and containing Ru; a second interlayer of a second non-magnetic material in overlying contact with the first interlayer and not containing Ru; and a third interlayer of a third non-magnetic material in overlying contact with the second interlayer and containing Ru. | 08-28-2008 |
20080213628 | Perpendicular recording media with Ta transition layer to improve magnetic and corrosion resistance performances and method of manufacturing the same - A perpendicular magnetic recording medium comprising a substrate, an underlayer, a Ta-containing seedlayer, a magnetic layer, wherein the underlayer comprises a soft magnetic material and the Ta-containing seedlayer is between the underlayer and the magnetic layer, and a process for improving corrosion resistance of the recording medium and for manufacturing the recording medium are disclosed. | 09-04-2008 |
20090211898 | MAGNETIC RECORDING MEDIA HAVING FIVE ELEMENT ALLOY DEPOSITED USING PULSED DIRECT CURRENT SPUTTERING - CoCrPtB is a conventional material used in some of the layers of a thin film magnetic media structure used for recording data in data storage devices such as hard drives. Typically the CoCrPtB layers used for magnetic media have high Cr and low B in bottom magnetic layers and low Cr and high B in top magnetic layers. In accordance with one embodiment of this invention and to improve media electrical performance, fifth elements, such as Ta, Nb and Hf, etc. were added to the CoCrPtB materials, resulting in CoCrPtB-X, to enhance the grain segregation. The five element CoCrPtB-X layers were deposited using a pulsed direct current sputter technique instead of conventional direct current sputtering techniques. The resulting magnetic media structure having CoCrPtB-X alloy layers exhibits an increase in coercivity Hc and improvement in recording performance. | 08-27-2009 |
20100165508 | MAGNETIC LAYERING FOR BIT-PATTERNED MEDIA - A perpendicular magnetic recording layer of a magnetic recording medium includes a plurality of bit-patterned magnetic islands, wherein each of the plurality of islands overlay a soft magnetic under-layer. Each of the magnetic islands includes a first magnetic sub-layer adjacent a second magnetic sub-layer, wherein the first sub-layer has a relatively high magnetic anisotropy that is greater than a magnetic anisotropy of the second sub-layer. The magnetic recording layer further includes a third sub-layer, which extends to connect each of the plurality of islands. The third sub-layer may have a magnetic anisotropy that is less than that of the second sub-layer of each of the magnetic islands and/or may serve as an interlayer, extending between the first sub-layer and the soft magnetic under-layer of the recording medium, and having a structure to help to produce the greater anisotropy first magnetic sub-layer. | 07-01-2010 |
20100209737 | MAGNETIC RECORDING MEDIA WITH ENHANCED WRITABILITY AND THERMAL STABILITY - Aspects are directed to recording media with enhanced magnetic properties for improved writability. Examples can be included or related to methods, systems and components that allow for improved writability while reducing defects so as to obtain uniform magnetic properties such as uniformly high anisotropy and narrow switching field distribution. Some examples include a recording medium with an exchange tuning layer inserted between the hard layer and the soft, semi-soft or thin semi-hard layer so as to maximize the writability improvement of the media. Preferably, the exchange tuning layer is granular and reduces or optimizes the vertical coupling between the hard layer and the soft, semi-soft or semi-hard layer of a magnetic recording or storing device. | 08-19-2010 |
20100221580 | Granular Perpendicular Media Interlayer For A Storage Device - An apparatus and method are provided for improving perpendicular magnetic recording media. The present invention provides media, and a method of fabricating media in a cost-effective manner, with a reduced ruthenium (Ru) content interlayer structure, while meeting media performance requirements. A perpendicular magnetic recording medium is provided comprising a non-magnetic substrate having a surface, and a layer stack situated on the substrate surface. The layer stack comprises, in overlying sequence from the substrate surface a magnetically soft underlayer; an amorphous or crystalline, non-magnetic seed layer; an interlayer structure for crystallographically orienting a layer of a perpendicular magnetic recording material situated on the underlayer; and at least one crystallographically oriented, magnetically hard, perpendicular magnetic recording layer situated on the interlayer structure. The interlayer structure is a stacked structure comprising, in overlying sequence: a chromium alloy situated on the seed layer; and an upper interlayer situated on the chromium alloy. | 09-02-2010 |
20120141836 | GRANULAR PERPENDICULAR MEDIA INTERLAYER FOR A STORAGE DEVICE - An apparatus and method are provided for improving perpendicular magnetic recording media. The present invention provides media, and a method of fabricating media in a cost-effective manner, with a reduced ruthenium (Ru) content interlayer structure, while meeting media performance requirements. A perpendicular magnetic recording medium is provided comprising a non-magnetic substrate having a surface, and a layer stack situated on the substrate surface. The layer stack comprises, in overlying sequence from the substrate surface a magnetically soft underlayer; an amorphous or crystalline, non-magnetic seed layer; an interlayer structure for crystallographically orienting a layer of a perpendicular magnetic recording material situated on the underlayer; and at least one crystallographically oriented, magnetically hard, perpendicular magnetic recording layer situated on the interlayer structure. The interlayer structure is a stacked structure comprising, in overlying sequence: a chromium alloy situated on the seed layer; and an upper interlayer situated on the chromium alloy. | 06-07-2012 |
20120219827 | Stack Including a Magnetic Zero Layer - A stack including a crystallographic orientation interlayer, a magnetic zero layer disposed on the interlayer, and a magnetic recording layer disposed on the magnetic zero layer is disclosed. The magnetic zero layer is non-magnetic or has a saturation magnetic flux density (B | 08-30-2012 |
20130052485 | RECORDING STACK WITH A DUAL CONTINUOUS LAYER - A perpendicular magnetic recording stack with a dual continuous layer and a method of manufacturing the same. The perpendicular magnetic recording stack includes a substrate, one or more magnetic granular recording layers, and a dual continuous layer having first and second continuous layers. The first continuous layer, disposed between the second continuous layer and the magnetic granular recording layers, has an intermediate lateral exchange coupling, which is higher than the lateral exchange coupling of the magnetic granular layers. The second continuous layer has a higher lateral exchange coupling than the first continuous layer. | 02-28-2013 |
20140186658 | Interlayer comprising chromium-containing alloy - An apparatus and method are provided for improving perpendicular magnetic recording media. The present invention provides media, and a method of fabricating media in a cost-effective manner, with a reduced ruthenium (Ru) content interlayer structure, while meeting media performance requirements. A perpendicular magnetic recording medium is provided comprising a non-magnetic substrate having a surface, and a layer stack situated on the substrate surface. The layer stack comprises, in overlying sequence from the substrate surface a magnetically soft underlayer; an amorphous or crystalline, non-magnetic seed layer; an interlayer structure for crystallographically orienting a layer of a perpendicular magnetic recording material situated on the underlayer; and at least one crystallographically oriented, magnetically hard, perpendicular magnetic recording layer situated on the interlayer structure. The interlayer structure is a stacked structure comprising, in overlying sequence: a chromium alloy situated on the seed layer; and an upper interlayer situated on the chromium alloy. | 07-03-2014 |
Patent application number | Description | Published |
20080222585 | INTERLEAVED VOLTAGE CONTROLLED OSCILLATOR - A design structure embodied in a machine readable medium used in a design process includes an interleaved voltage-controlled oscillator, including a ring circuit of main logic inverter gates; a plurality of delay elements connected in parallel with a selected sequence of the main logic inverter gates; wherein each delay element comprises a feedforward section, comprising controls for regulating signal transmission through feedforward elements responsive to one or more control voltages; and a proportional section for regulating signal transmission through at least one logic inverter gate; at least one temperature compensation circuit responsive to a compensating voltage input that is proportional to temperature; an electronic circuit in communication with the temperature compensation circuit and configured to provide a voltage signal responsive to temperature; an amplifier in connection with the electronic circuit to amplify the voltage signal; and a DC offset generator configured to adjust the voltage of the amplified voltage signal. | 09-11-2008 |
20090002038 | Phase Locked Loop with Stabilized Dynamic Response - A hybrid phase locked loop (PLL) circuit for obtaining stabilized dynamic response and independent adjustment of damping factor and loop bandwidth is provided. The hybrid PLL circuit of the illustrative embodiments includes the resistance/capacitance (RC) filter elements of a conventional RC PLL and the feed-forward path from the output of the phase frequency detector to the voltage controlled oscillator (VCO). The hybrid PLL essentially enhances the performance of the conventional feed-forward PLL by providing the RC filter whose components can be weighted to provide a dynamic response that is significantly less sensitive to parameter variation and which allows loop bandwidth optimization without sacrificing damping. | 01-01-2009 |
20090125262 | Absolute Duty Cycle Measurement Method and Apparatus - A method and apparatus for measuring the absolute duty cycle of a signal are provided. A non-inverted path from a signal source is selected and various DCC circuit setting indices are cycled through until a divider, coupled to the output of the DCC circuit, fails. A first minimum pulse width at which the divider fails is then determined based on the index value of the DCC circuit at the time of the failure. An inverted path from the signal source is selected and the various DCC circuit setting indices are cycled through again until the divider fails. A second minimum pulse width at which the divider fails is then determined based on the index value of the DCC circuit at the time of this second failure. The duty cycle is then calculated based on a difference of the first and second minimum pulse width values. | 05-14-2009 |
20090128133 | Duty Cycle Measurement Method and Apparatus for Various Signals Throughout an Integrated Circuit Device - A method and apparatus for measuring the absolute duty cycle of a signal anywhere on an integrated circuit device are provided. The mechanism employs a circuit having a plurality of substantially identical pulse shaper elements, each of which expand the pulse of an input signal whose duty cycle is to be measured by a same amount. The outputs of the pulse shaper elements may be coupled to substantially identical divider circuits whose outputs are coupled to a multiplexer that selects two inputs for output to a set of master/slave configured flip-flops, one input serving as a clock and the other as data to the flip-flops. The flip-flops sample the divider outputs selected by the multiplexer to detect if the dividers have failed or not. The outputs of the flip-flops are provided to an XOR gate which outputs a duty cycle signal indicative of the duty cycle of the input signal. | 05-21-2009 |
20090128206 | Apparatus and Method for Obtaining Desired Phase Locked Loop Duty Cycle without Pre-Scaler - An apparatus and method for obtaining a desired phase locked loop (PLL) duty cycle without a pre-scaler are provided. The PLL circuit of the illustrative embodiments utilizes two separate loops that simultaneously operate on the VCO. One loop ensures the frequency and phase lock while the other loop ensures the duty cycle lock. The VCO is modified to have an additional control port to adjust the duty cycle. Thus, the VCO has one control port for performing frequency adjustment and one control port for duty cycle adjustment. As a result, both the duty cycle and the frequency may be controlled using the VCO of the PLL circuit of the illustrative embodiments so as to achieve any desired duty cycle output without requiring a VCO pre-scaler circuit or duty cycle correction circuit. | 05-21-2009 |
20090160492 | Glitchless Clock Multiplexer Optimized for Synchronous and ASynchronous Clocks - A circuit for switching clock signals with logic devices using a glitchless clock multiplexer optimized for synchronous and asynchronous clocks. The circuit comprises an asynchronous clock group and one or more synchronous clock group(s). The asynchronous group comprises a plurality of high frequency glitchless control (HFGC) blocks for asynchronous clock sources. Each synchronous group comprises a plurality of HFGC blocks for synchronous clock sources. The circuit comprises a multiplexer for receiving delayed input clock signals from HFGC blocks for asynchronous clock sources and from HFGC blocks for synchronous clock sources. A switching latency from a first input clock signal belonging to a synchronous group to a second input clock signal belonging to the same synchronous group is one clock cycle or less of the second input clock signal. Switching latency is the period in which no clock pulse appears at the final output of the circuit. | 06-25-2009 |