Abstract: A patterned magnetic recording medium, accessible by a magnetic recording head, including a plurality of tracks, a width direction of each track and that of the magnetic recording head being of a skew angle. The patterned magnetic recording medium includes a plurality of magnetic dots, each corresponding to a recording bit, formed on a non-magnetic material. The plurality of magnetic dots are arranged in a plurality of arrays, each array corresponding to one of the tracks. Every N adjacent magnetic dots of the array define a polygon, one side thereof being parallel to the corresponding track, and another side thereof being parallel to a direction corresponding to the skew angle of the corresponding track.

Abstract: A switching power supply exhibits high conversion efficiency and facilitates reducing the size thereof. The switching power supply includes a half-bridge circuit including a first series circuit formed of switching devices Q1 and Q2 and connected between the output terminals of a DC power supply; and a second series circuit connecting primary inductance Lr1 of transformer T1, primary inductance Lr2 of transformer T2 and capacitor Cr in series. The second series circuit is connected between the output terminals of the half-bridge circuit, and is made to conduct a series resonance operation. The switching devices Q1 and Q2 is controlled at the ON-duties of 0.5 for reducing the breakdown voltages of rectifying diodes D1 and D2 on the secondary side of transformers T1 and T2 and for improving the conversion efficiency of the switching device.

Abstract: A method of manufacturing a magnetic recording medium. The method includes altering magnetic characteristics of a magnetic recording layer at positions corresponding to concave portions of a mask layer by ion implantation or exposure to an activated halogen-containing reactive gas, via a mask layer on which a concavo-convex pattern is formed. The concavo-convex pattern is formed by forming a separating portion that magnetically separates magnetic portions of the magnetic recording layer in positions corresponding to convex portions of the mask layer. A resist material configuring the mask layer allows the shape of the concavo-convex pattern to vary after the formation of the concavo-convex pattern. A taper angle of a stepped portion marking the boundaries between the concave and convention portions of the concavo-convex pattern, when starting the alteration of magnetic characteristics of the magnetic recording layer, is between 66° and 88°.

Abstract: A magnetic recording medium comprises a data region for recording data and a servo region that is disposed adjacent to the data region and has recorded information for controlling a magnetic head. The data region has a pattern of dots separated from each other by grooves or nonmagnetic material. The servo region lacks the pattern of dots, and includes magnetic information written in a flat region. The magnetic recording medium can be formed by a method that does not need a separate process of writing servo information.

Abstract: A method of manufacturing a magnetic recording medium having a discrete track structure enables the discrete track structure to be fabricated in a simple method with good productivity while maintaining satisfactory accuracy of the discrete track structure and holding favorable magnetic separation performance between tracks. The method comprises steps of: forming an aluminum film on a nonmagnetic substrate; executing an anodizing process on the aluminum film to form an alumina layer including nano-holes in a self-organizing manner; forming a resist pattern exposing recording track regions; and depositing a magnetic material in the nano-holes in the recording track regions. The method can further comprise a step of forming recessed parts at positions of the nano-holes to be formed in the anodizing process. The method can further comprise a step of forming a first underlayer of titanium and a second underlayer of gold.

Abstract: A perpendicular magnetic recording medium includes a soft magnetic backing layer, an underlayer, a nonmagnetic intermediate layer, and a magnetic recording layer sequentially deposited on a nonmagnetic substrate. The underlayer can contain cobalt, nickel, and iron and have an fcc structure and exhibit soft magnetic property. The underlayer preferably contains nickel in a range of 30 to 88 at % and iron in a range of 0.1 to 22 at %. The underlayer can further contain Si, B, Nb, N, Ta, Al, Pd, Cr, or Mo. The nonmagnetic intermediate layer preferably contains at least one element selected from Ru, Re, Pd, Ir, Pt, and Rh. The magnetic recording layer preferably has a granular structure. A seed layer can be further provided between the soft magnetic backing layer and the underlayer.

Abstract: The present invention relates to a magnetic thin film containing a L11 type Co—Pt—C alloy in which atoms are orderly arranged, and can realize an order degree excellent in regard to the L11 type Co—Pt—C alloy to achieve excellent magnetic anisotropy of the magnetic thin film. Therefore, in the various application devices using the magnetic thin film, it is possible to achieve a large capacity process and/or a high density process thereof in a high level.

Abstract: This invention provides a magnetic recording medium evaluation apparatus and evaluation method which yield results having good correlation with error rate measurements even when comparing media with different structures. Signals from a function generator are recorded in a magnetic recording medium. The recording signals are also passed through a first digital filter to obtain ideal restored signals. Reproduced signals from the magnetic recording medium are sampled in synchronization with the output from the function generator, and the discrete signals are passed through a second digital filter to obtain restored signals. The outputs from the first and second digital filters are input to an operational amplifier, and the difference between the restored signals and the ideal restored signals is taken for each sampling of the recording signals. The signal-to-noise ratio of the ideal restored signal to the average of the absolute value of this difference is used to evaluate signal quality.

Abstract: A method of manufacturing a master disk for magnetic transfer is provided in which a pattern configuration does not change and burrs that require a polishing process are not generated. The method of manufacturing a master disk for magnetic transfer can include preparing a nonmagnetic body, forming a pattern of recessed parts on the nonmagnetic body, and forming a ferromagnetic material layer by depositing a ferromagnetic material on a surface of the nonmagnetic body having the pattern of recessed parts thereon. The method can further include forming a pattern of ferromagnetic material layers at the recessed parts by removing an excess portion of the ferromagnetic layer without using a mask. An etching rate of the nonmagnetic body can be larger than an etching rate of the ferromagnetic material layer in the operation of forming a pattern of ferromagnetic material layers at the recessed parts.

Abstract: A method for manufacturing a semiconductor module, includes the steps of preparing a board; mounting a semiconductor device on the second metal foil; placing a resin case onto the board for surrounding a first metal foil, an insulating sheet, the second metal foil, and the semiconductor device; pouring a resin in a paste form into the case to fill a space relative to the first metal foil, insulating sheet, the second metal foil and the semiconductor device; and heat-curing the resin. A bottom end of a peripheral wall of the case is located above a bottom surface of the first metal. The bottom surface of the first metal foil and the resin form a flat bottom surface to contact an external mounting member.

Abstract: A method of producing a perpendicular magnetic recording medium with a magnetic recording layer formed from ferromagnetic crystal grains and oxide-including non-magnetic crystal grain boundaries and provided on a non-magnetic substrate. The method is initiated by forming the magnetic recording layer by a reactive sputtering method using rare gas containing 2% by volume to 10% by volume (both inclusively) of oxygen gas at an initial stage of film formation. The method continues by successively forming the magnetic recording layer by reactive sputtering while reducing the concentration of the oxygen gas. The method may further include forming an undercoat layer of Ru or a Ru-alloy under the magnetic recording layer. In this manner, a granular magnetic layer having high characteristic coercive force (Hc) can be formed, while reducing the amount of expensive Pt or Ru required.

Abstract: A semiconductor device having an IGBT includes: a substrate; a drift layer and a base layer on the substrate; trenches penetrating the base layer to divide the base layer into base parts; an emitter region in one base part; a gate element in the trenches; an emitter electrode; and a collector electrode. The one base part provides a channel layer, and another base part provides a float layer having no emitter region. The gate element includes a gate electrode next to the channel layer and a dummy gate electrode next to the float layer. The float layer includes a first float layer adjacent to the channel layer and a second float layer apart from the channel layer. The dummy gate electrode and the first float layer are coupled with a first float wiring on the base layer. The dummy gate electrode is isolated from the second float layer.

Abstract: A super-junction semiconductor substrate is configured in such a manner that an n-type semiconductor layer of a parallel pn structure is opposed to a boundary region between an active area and a peripheral breakdown-resistant structure area. A high-concentration region is formed at the center between p-type semiconductor layers that are located on both sides of the above n-type semiconductor layer. A region where a source electrode is in contact with a channel layer is formed over the n-type semiconductor layer. A portion where the high-concentration region is in contact with the channel layer functions as a diode. The breakdown voltage of the diode is set lower than that of the device.

Abstract: A magnetic recording medium exhibiting a high recording density performance is disclosed. The perpendicular magnetic recording medium has a soft magnetic underlayer, a first seed layer, a second seed layer, an intermediate layer, a granular magnetic recording layer, a non-granular magnetic recording layer, a protective layer, and a lubricant layer laminated on a nonmagnetic substrate in this order. The first seed layer contains cobalt, nickel, and at least one element selected from a group consisting of Si, Cr, V, Zr, Nb, Ta, Ti, Cu, and Mo, and the second seed layer contains nickel, chromium, and at least one element selected from a group consisting of Si, V, Zr, Nb, Ta, Ti, Cu, and Mo.

Abstract: A method of magnetic transfer, including placing a first medium in contact with a second medium, pressing the first and second media together to form an adhered body, applying a magnetic field to the adhered body, and moving the magnetic field relatively to the adhered body, so as to transfer information from the first medium to the second medium. Then the monitoring of the adhered body is performed to detect existence of an air bubble between the first and second media.

Abstract: A semiconductor device includes a silicon substrate having a first major surface and a second major surface opposite to the first major surface, a drift layer and a collector layer formed in sequence in the silicon substrate from the first major surface, and an aluminum silicon film formed on the second major surface. The drift layer is of a first conductivity type, and is surrounded by a semiconductor layer of a second conductivity type including the collector layer.

Abstract: A semiconductor device includes an outer resin case having a peripheral wall and terminal mounting holes formed in the peripheral wall, and a layer assembly provided in the outer resin case. The layer assembly includes a semiconductor chip, an insulating circuit board on which the semiconductor chip is mounted, and a heat-dissipating metal base. External terminals having leg portions are arranged in mounting holes of the peripheral wall, and are press-fitted into the terminal-mounting holes. Bonding wires connect the terminal leg portions and a conductive pattern of the insulating circuit board or the semiconductor chip.

Abstract: An object of the present invention is to provide a method of manufacturing a glass substrate containing alkali metals. A glass substrate manufactured by the method exhibits excellent performances including durability by virtue of suppressing elution of alkali metals. A method comprises a step of immersing a glass material in an aqueous solution containing a formate to suppress elution of component of the glass material.

Abstract: An integrated control circuit for controlling a switching power supply, a switching power supply incorporating the same, and a method of controlling the switching power supply, where the control IC includes a current comparator that detects current flowing through a switching device, a flip-flop circuit that controls the ON-period of the switching device, an averaging circuit that converts the peak load current value to a time-average, a comparator that detects an overloaded state from the load current, a delay circuit that sets a time from detecting the overcurrent state to stopping the switching operation, a latch circuit that stops the switching operation for a period of time, a first reference voltage supply used in the current comparator, which has a higher voltage value than a second reference voltage supply used in the comparator.

Abstract: A switching power supply system, in which a DC voltage obtained by full-wave rectification of an AC voltage is turned on and off by a switching device, converted to a desired DC voltage and outputted, includes a slope compensating circuit and an overcurrent protecting circuit, and a full-wave rectified voltage inputted to a terminal Tm is subtracted from a reference voltage Vref inputted to a terminal Tr to produce a reference voltage waveform signal (OCP correction value) Vocp to eliminate the influence of slope compensation. The reference signal of the overcurrent protection circuit is varied by a signal having a reverse phased waveform relative to the phase of the full-wave rectified waveform. This enables highly accurate overcurrent protection with a net overcurrent protection level unaffected by the slope compensation varied by the input voltage when the system is operated in a current mode.