Abstract: An abrasive composition is provided comprising an oxidizing agent and abrasive particles which have a mean particle size of 2 .mu.m or less, wherein each of the abrasive particles comprises (i) at least one oxide selected from aluminum oxide and silicon oxide and (ii) cerium oxide in an amount of 5% to 40% by weight in terms of cerium based on the oxide (i). A method for polishing and planarizing a metal layer formed on a semiconductor substrate using the abrasive composition is also provided.

Abstract: Disclosed is an abrasive particle having an average particle size of not more than 2 .mu.m and comprising 100 parts by weight of aluminum oxide and/or silicon oxide and 5 to 25 parts by weight of cerium in the form of cerium oxide. A method for producing the same, and a method for planarizing an insulating film on a semiconductor substrate using the abrasive particles are also disclosed.

Abstract: When plug is fitted to adapter, optical fiber is inserted to an alignment hole for the optical fiber. By providing a taper at the entrance thereof, even if the tip of the optical fiber is deviated from the central position, the deviation is absorbed to make it possible for the optical fiber to be inserted smoothly. When two plugs is fitted to adapter, the tip of one optical fiber is confronted with the other one in the alignment hole, and excessive length L.sub.1 -L.sub.2 is pushed into the two optical fiber-bending spaces with a suitable distribution, thus the optical fiber buckles therein. The end face of the optical fiber is subjected to flat surface-polishing, removal of ripples after being cleaved, or chamfer grinding after being cleaved. The buckling portion of the optical fiber is coated with carbon or the like.

Abstract: A semiconductor memory device including a memory cell array, bit lines, and sense amplifier groups. The memory cell array is composed of a plurality of memory cells arranged roughly in a matrix pattern. A plurality of the memory cells arranged in a row are activated in response to a row address decode signal. A pair of the bit lines are provided for each column. The data of the corresponding activated memory cells are transmitted to the bit line pair. Each of the sense amplifier groups has n-units of sense amplifiers each connected to the bit line pair, to sense and amplify data read to the bit line pair connected thereto. The respective reference potential terminals of the sense amplifiers of each of the sense amplifier groups are connected to a single common node which can be connected to a reference potential via a sense amplifier activating transistor turned on in response to a row address signal.

Abstract: The semiconductor device comprises: an internal supply voltage deboosting circuit for inputting an external supply voltage, deboosting the inputted external supply voltage, and outputting a deboosted voltage as an internal supply voltage; a first control circuit for deactivating the internal supply voltage deboosting circuit when the external supply voltage is lower than a predetermined value; and a second control circuit for outputting the external supply voltage as the internal supply voltage when the external supply voltage is lower than the predetermined value. When the external supply voltage is lower than a predetermined value, since the internal supply voltage deboosting circuit is deactivated by the first control circuit, the current consumption can be reduced. Further, since the external supply voltage is outputted as the internal supply voltage by the second control circuit, the deboosting operation is not required.

Abstract: The present invention provides a magnetic recording medium comprising, on a non-magnetic substrate, a magnetic layer containing magnetic fine powder and a binder, wherein the magnetic layer contains alumina powder having an average particle size of at most 1 .mu.m and containing at least one oxide of element selected from the group consisting of Ge, P, Sn, Nb, Ta, Mo and W in an amount of 0.1 to 10 parts by weight per 100 parts by weight of alumina. The magnetic recording medium of the present invention has good durability and good abrasion resistance of the magnetic layer, and good magnetic characteristics, good surface smoothness and a good cleaning effect on a magnetic head.

Abstract: A non-aqueous electrolyte secondary cell having a negative electrode, a positive electrode and a non-aqueous electrolytic solution, in which a carbonaceous material is used as an active negative-electrode material, is disclosed. The negative electrode is constituted by a carbon sintered mass obtained on sintering the carbonaceous material or a carbon sintered mass-current collector composite material. The secondary cell is improved in the amount of the active material packed in the negative electrode, energy density and in the charging/discharging efficiency. If the carbon sintered mass-current collector composite material is employed for the negative electrode, further improvement in the electrical conductivity and charging/discharging efficiency in the negative electrode is achieved.

Abstract: The present invention discloses a process for preparing a fine-particulate metal hydroxide comprising aluminum hydroxide as a major component which comprises continuously supplying water and a mixture of an aluminum alkoxide and at least one alkoxide of a metal selected from Mg, Ca, La, Fe, Si, Ti and Zr, to a high shear rate stirring area and a process for preparing a fine-particulate metal oxide comprising aluminum oxide as a major component which comprises drying and then calcining said metal hydroxide at 500.degree.-1500.degree. C.

Abstract: Aluminum hydroxide containing no coarse particle is prepared by continuously supplying at least one compound selected from the group consisting of aluminum alkoxides and aluminum alkoxide derivatives which are prepared by chemically modifying aluminum alkoxides, and water under high shear rate stirring.

Abstract: This invention provides a plasma CVD method aimed at forming an amorphous silicon thin film on a large-area substrate at a high speed and also an apparatus therefor. The method and apparatus are characterized by a reaction vessel, means for feeding a reactant gas to the reaction vessel and discharging the same, discharging electrodes accommodated in the reaction vessel, a source for supplying power for glow discharge to the discharging electrodes, two pairs of solenoid coils arranged on opposite sides of said reaction vessel and so disposed that the axes thereof perpendicularly intersect each other as well as perpendicularly the electric field formed between the discharging electrodes, and an AC source for supplying power to said solenoid coils for magnetic field generation, whereby an amorphous silicon thin film is formed on a substrate held to intersect perpendicularly the electric field between the discharging electrodes.

Abstract: A plasma CVD apparatus whose discharge electrode is a single line member bent in a U shape in an alternating manner and in which a substrate to be processed is held substantially in parallel to the discharge electrode. The electric field around the electrode becomes stronger and the intensity distribution of this field becomes even. As a result, a product film formed on the substrate surface has a uniform thickness, and the film can be formed at high speeds.

Abstract: Alumina powder having a .theta.-alumina content of at least 70% by weight and an average primary particle size at least 0.1 .mu.m and containing a tungsten compound in an amount of 0.1 to 5% by weight in terms of tungsten oxide based on alumina can be used as an abrasive for a magnetic recording medium having good properties.

Abstract: A plasma-chemical vapor-phase epitaxy system or a chemical vapor deposition (CVD) system can produce a large thin film of good quality. The CVD system includes a vacuum container having a quartz glass window, a substrate disposed within the vacuum container as opposed to the window, an antenna type discharge electrode disposed outside of the vacuum container as opposed to the window, and a high-frequency power supply for feeding electric power to the same electrode. In this way, by disposing an electrode outside of a container and exciting the reaction gas with high-frequency electromagnetic waves, a large thin film of good quality can be formed.

Abstract: In a semiconductor memory device having plural pairs of bit lines and plural sense amplifiers, a gate electrode of a sense amplifier transistor for sensing potential of a first side of a first bit line pair is formed with an extension portion extending under and along the first side of a second bit line pair. A capacitance C.sub.B formed between the extension of the gate electrode and the first side of the second bit line pair is determined to be equal or larger than capacitance C.sub.A formed between the first side of the first bit line pair and the gate electrode. Since the potential of the first side of the bit line pair fluctuates roughly in phase with that of the second side of the same bit line pair, a harmful influence due to interference noise can be reduced, without increasing the chip layout area, by only modifying the shapes of the gate electrodes of the sense amplifier transistors.

Abstract: A magnetic recording medium comprising a non-magnetic substrate and a magnetic layer which comprises magnetic powder, a binder and alumina powder having an average primary particle size of not larger than 0.3 .mu.m and containing at least one oxide selected from the group consisting of oxides of silicon, magnesium, lanthanum and zirconium in an amount of 0.05 to 5 parts by weight per 100 parts by weight of alumina, which medium has improved durability, abrasion resistance and surface smoothness of a magnetic layer and good cleaning effect on a magnetic head.

Abstract: A polishing composition for metallic materials, which comprises water, an alumina polishing agent, and a polishing accelerator, wherein the polishing accelerator is at least one selected from the group consisting of chromium(III) nitrate, lanthanum nitrate, ammonium cerium(III) nitrate, and neodymium nitrate. The polishing composition has a high polishing efficiency and provides a good surface smoothness.

Abstract: Two single mode optical fibers are reduced in diameter over a predetermined length to form reduced-diameter portions whose center portions have different diameters. The two optical fibers are intersected at a small angle to each other substantially centrally of their reduced-diameter portions and then are fused together at the intersecting portions and the fused portions of the two optical fibers are heated and stretched to provide an optical coupler having a desired coupling ratio.

Abstract: Two single mode optical fibers are stretched to form prestretched portions of different diameters, and then the optical fibers are fused together at their prestretched portions to form a coupling region which is stretched to obtain a wide-band optical fiber coupler of a desired splitting ratio.

Abstract: In a method of making an optical fiber coupler through heat elongation of optical fibers, the performance of the coupled optical fibers is measured after the optical fibers are heat elongated at least once, and based on the measured elongation length and the performance of the coupled optical fibers, a functional equation representing their relationship is determined by approximate calculation. The functional equation is used to calculate an elongation length which provides the intended performance of the coupled optical fibers, and then the optical fibers are heat elongated to the calculated length.

Abstract: A fiber coupler includes first and second optical fiber groups and a fused-elongated region. The first optical fiber group is obtained by parallelly arranging a plurality of optical fibers on a single plane, a coating of each of the optical fibers being removed throughout a predetermined portion at the same position as that of an adjacent optical fiber in a longitudinal direction. The second optical fiber group is obtained by parallelly arranging adjacent optical fibers on a predetermined plane parallel to an arrange plane of the first optical fiber group at the same pitch as that of the first optical fiber group, a coating of each of the optical fibers being removed throughout a predetermined portion at the same position as that of an adjacent optical fiber in a longitudinal direction as the first optical fiber group.