Alps Electric Co., Ltd.

Kyoto University

Mitsubishi Electric Corporation

Rohm Co., Ltd.

Hamamatsu-Photonics K.k.

Tdk Corporation

Other

Tokyo Electron Limited

Lg Philips Lcd Co., Inc.

Horiba Stec, Co., Ltd.

Frontec Incorporated

Hitoshi Kitagawa

Susumu Noda

Makoto Sasaki

Takashi Asano

Seiichi Takayama

Kazuyoshi Hirose

Tsuneyuki Okabe

Shuji Moriya

Hirofumi Fukui

Akiyoshi Watanabe

Tetsuo Shimizu

Hiroyuki Ebi

Yong Liang

Tadahiro Ohmi

Yasuhiko Kasama

Akira Nakano

Osamu Yoshida

Yoshinori Tanaka

Chisato Iwasaki

Koichi Fukuda

Naoki Ito

Masanori Miyazaki

Tomofumi Oba

Masahiro Aoki

Masaru Kubota

To provide a two-dimensional photonic crystal surface emitting laser capable of improving characteristics of light to be emitted, in particular, optical output power. The two-dimensional photonic crystal surface emitting laser includes: a two-dimensional photonic crystal including a plate-shaped base member and modified refractive index regions where the modified refractive index regions have a refractive index different from that of the plate-shaped base member and are two-dimensionally and periodically arranged in the base member; an active layer provided on one side of the two-dimensional photonic crystal; and a first electrode and a second electrode provided sandwiching the two-dimensional photonic crystal and the active layer for supplying current to the active layer, where the second electrode covers a region equal to or wider than the first electrode.

Two-dimensional photonic crystal surface emitting laser

To provide a two-dimensional photonic crystal surface emitting laser capable of improving characteristics of light to be emitted, in particular, optical output power. The two-dimensional photonic crystal surface emitting laserX includes: a two-dimensional photonic crystalincluding a plate-shaped base memberand modified refractive index regionswhere the modified refractive index regionshave a refractive index different from that of the plate-shaped base memberand are two-dimensionally and periodically arranged in the base member; an active layerprovided on one side of the two-dimensional photonic crystal; and a first electrodeA and a second electrodeprovided sandwiching the two-dimensional photonic crystaland the active layerfor supplying current to the active layer, where the second electrodecovers a region equal to or wider than the first electrodeA, wherein the first electrodeA is formed so as to supply the current to the active layerwith a different density depending on the in-plane position on the first electrodeA.

A two-dimensional photonic-crystal surface-emitting laserincludes: a two-dimensional photonic crystal (two-dimensional photonic crystal layer) including a plate-shaped base bodyhaving a predetermined size in which modified refractive index areaswhose refractive index differs from the base body are periodically arranged in a two-dimensional pattern; an active layerprovided on one side of the two-dimensional photonic crystal; and first and second electrodesandfacing each other across the two-dimensional photonic crystal and the active layer, for supplying an electric current to the active layer. The modified refractive index areasare provided in such a manner that the in-plane occupancy of those areasin the base bodydecreases, or the lattice constant for those areasincreases, in the direction from an outer edge toward the center of a current passage regionwhich is a region where the electric current passes through the two-dimensional photonic crystal. With this configuration, a stable laser oscillation can be obtained even when a temperature distribution which is lower at the outer edge and higher at the center of the current passage region is formed within the two-dimensional photonic crystal.

Two-dimensional photonic-crystal surface-emitting laser

Holesare created in a slab-shaped body. On the first surfaceof the body, the holesare arranged at the lattice points of a triangular lattice. On the second surface, they are arranged at the lattice pointslocated at positions corresponding to the gravity center of a triangular lattice. Three air columnsA obliquely extend from each lattice pointto the nearest three lattice points. Similarly, three air columnsA obliquely extend from each lattice pointto the nearest three lattice points. In this construction, a periodic structural unitconsisting of three holes is created within the bodyand this unit has a C-symmetrical shape at any sectionparallel to the body. Due to this symmetry and the obliquely extending form of the air columnA, a complete PBG with a large width is obtained. In one embodiment, a broad complete PBG whose width equals 15% of its middle value is obtained.

Two-dimensional photonic crystal

A thermal mass flow meter and a thermal mass flow control device addresses a thermal siphon error, even if they are in a compact and inexpensive structure, without using a flow path converting block. A control computing process portion is configured to correct a measurement error caused by thermal siphon by calculating a correction value based on a measurement value at time of depressurizing fluid flow path and flow rate measuring conduit to an atmospheric pressure or less, a difference between the measurement value and a measurement value at time of charging an actual fluid into the flow rate measuring conduit, kind of the actual fluid, pressure at time of charging the actual fluid, and flow ratio of the fluid flowing in the fluid flow path and the flow rate measuring conduit, storing the correction value, and correcting an actual measured output flow value by the stored correction value.

Thermal type mass flow meter, and thermal type mass flow control device

The present invention provides a two-dimensional photonic crystal in which an absolute photonic band gap (PBG), i.e. a photonic band gap that is effective for both the TE-polarized light and the TM-polarized light within a predetermined wavelength range, is created with an adequate bandwidth. The bodyis provided with holesarranged in a triangular lattice pattern, where the basic shape of the hole is an equilateral triangle. This shaping and arranging of the holes creates an absolute PBG. Each corner of the equilateral triangle is cut along an arc to leave an adequate distance between the neighboring holes (i.e. an adequate width of the connecting portion of the body). This design makes it possible to enlarge each holewhile ensuring an adequate strength of the two-dimensional photonic crystal. This construction creates an absolute PBG having a large width.

The present invention intends to provide a two-dimensional photonic crystal having a wide photonic band gap (PBG). In a slab-shaped body, a number of holes, whose sectional shape on a plane parallel to the slab surface is an equilateral triangle, are periodically arranged in a triangular lattice pattern. The upper and lower sides of the holesare covered with the material of the body. The aforementioned sectional shape is uneven along the direction perpendicular to the slab surface. This construction expands the PBG for TM-polarized light and thereby increases its energy region overlapping with the PBG for TE-polarized light. This overlapping section is the complete PBG. If a ray of light whose wavelength corresponds to an energy level within the complete PBG, neither the TE-polarized nor TM-polarized component of the light can be propagated through the photonic crystal. Therefore, even if a waveguide and/or a resonator is provided in the photonic crystal, the light having the aforementioned wavelength will never leak from the waveguide or resonator into the photonic crystal.

Two-dimensional photonic crystal and optical device using the crystal

Zero point shift based on thermal siphon effect occurring actually when a substrate is processed is detected accurately and corrected suitably. The semiconductor fabrication system comprises a gas supply passage () for supplying gas into a heat treatment unit (), an MFC () for comparing an output voltage from a detecting unit for detecting the gas flow rate of the gas supply passage with a set voltage corresponding to a preset flow rate and controlling the gas flow rate of the gas supply passage to the set flow rate, and a control unit (). The control unit replaces gas in the MFC by gas which is to be used at least for processing a substrate before the substrate is processed, detects the output voltage from the MFC under a state where valves () provided in the upstream and the downstream of the MFC are closed and stores the detected output voltage in a storage unit, corrects the set voltage corresponding to the flow rate of gas to be used for processing the substrate based on the output voltage from the MFC stored in the storage unit at the time of processing the substrate, and sets the corrected set voltage in the MFC.

Semiconductor fabrication system, and flow rate correction method and program for semiconductor fabrication system

A two-dimensional photonic crystal slab having a photonic band gap common to a light beam in the TE-like mode and a light beam in the TM-like mode includes a slab member containing a high refractive index material and low refractive index sectors, arranged in the slab member in a triangular pattern, having a triangular prism shape. The two-dimensional photonic crystal slab further includes a linear defect section that is a disordered portion in a periodic structure of a photonic crystal and extends in the &#x393;-J direction. Light beams in the TE-like mode and light beams in the TM-like mode can be propagated through the waveguide section. A two-dimensional photonic crystal waveguide includes the two-dimensional photonic crystal slab.

Two-dimensional photonic crystal slab, two-dimensional photonic crystal waveguide, and optical device

A photonic crystal device having a variable bandgap includes a periodic structural body including a plurality of separate dielectric members arranged at intervals. The dielectric members are formed of a high-dielectric material. A variable-dielectric-constant material whose dielectric constant is varied by an electric field is filled in the spaces between the dielectric members. Electrodes are also provided for applying an electric field to the variable-dielectric-constant material.

Photonic crystal device having variable bandgap, optical waveguide using the same, and optical multiplexing/demultiplexing device using the same

A thin-film capacitor device for performing temperature compensation is manufactured by layering a first dielectric thin-film and a second dielectric thin-film, wherein the second dielectric thin-film has a thickness t , wherein t &equals;&lcub;&egr; &tgr; /(C/S)&rcub;&middot;&lcub;1/(&tgr;/&kgr;)&rcub;, wherein C/S represents a sheet capacitance, &egr; represents the dielectric constant of vacuum, &tgr; represents a desired temperature coefficient of capacitance, &tgr; represents the temperature coefficient of capacitance of the second dielectric thin-film, and &kgr; represents the relative dielectric constant of the second dielectric thin-film, a target value of a grain size of the second dielectric thin-film is determined by selecting the grain size satisfying the formula (&tgr;/&kgr;)/(&tgr; /&kgr; )>1, wherein &tgr; represents the temperature coefficient of capacitance of the principal crystal grain, and &kgr; represents relative dielectric constant of the principal crystal grain, and the second dielectric thin-film is deposited so that the grain size becomes the target value.

Thin-film capacitor device

In a method for manufacturing a thin-film capacitor for performing temperature compensation by layering a first dielectric thin-film and a second dielectric thin-film, wherein the second dielectric thin-film has a thickness t , wherein t &equals;&lcub;&isin; &tgr; /(C/S)&rcub;&middot;&lcub;1/(&tgr;/&kgr;)&rcub;, wherein C/S represents a sheet capacitance, &isin; represents the dielectric constant of vacuum, &tgr; represents a desired temperature coefficient of capacitance, &tgr; represents the temperature coefficient of capacitance of the second dielectric thin-film, and &kgr; represents the relative dielectric constant of the second dielectric thin-film, a target value of a grain size of the second dielectric thin-film is determined by selecting the grain size satisfying the formula (&tgr;/&kgr;)/(&tgr; /&kgr; )>1, wherein &tgr; represents the temperature coefficient of capacitance of the principal crystal grain, and &kgr; represents relative dielectric constant of the principal crystal grain, and the second dielectric thin-film is deposited so that the grain size becomes the target value.

Method for manufacturing thin-film capacitor for performing temperature compensation of junction capacitance of semiconductor device

A temperature-compensating thin-film capacitor includes a first dielectric thin-film having a specific inductive capacity of 4.0 or less and a linear thermal expansion coefficient of 50 ppm/&deg; C. or more, and includes a second thin-film capacitor having capacitance-temperature coefficient with an absolute value of 50 ppm/&deg; C. or less, in which the first and the second dielectric thin-films are placed between electrodes. The present thin-film capacitor design significantly reduces variations in capacitance due to manufacturing equipment tolerance. Also, miniaturization, thinning, and lightening of the thin-film capacitor is achieved. In another aspect of the invention, an electronic device having the temperature-compensating thin-film is provided. The temperature stability of the present thin-film capacitor is highly advantageous for incorporation into electronic devices such as a portable electronic device, microwave communication equipment.

Temperature-compensating thin-film capacitor and electronic device

The present invention provides a thin-film capacitor which can easily meet requirements of reduction in size, thickness, and weight and which can perform temperature compensation. In addition to the features described above, the present invention provides a thin-film capacitor having a superior Q factor in a high frequency band. The thin-film capacitor of the present invention has at least one first dielectric thin-film and at least one second dielectric thin-film having a dielectric constant different from that of the first dielectric thin-film, wherein these thin-films are provided between a pair of electrodes. In addition, in the present invention, the absolute value of the temperature coefficient of capacitance of the first dielectric thin-film is 50 ppm/&deg; C. or less, and the temperature coefficient of capacitance of the second dielectric thin-film is a negative value and has an absolute value of 500 ppm/&deg; C. or more.

Temperature compensating thin-film capacitor

In a thin-film-transistor-array substrate, a plurality of gate wires and a plurality of source wires are provided on the substrate to form a matrix; a pixel is formed on each of a plurality of areas each enclosed by two adjacent ones of the gate wires and two adjacent ones of the source wires; the pixel includes a thin-film-transistor having: a gate electrode formed as a portion of the gate wire; a source electrode formed as a portion of the source wire; and a drain electrode connected to a pixel electrode formed on an insulation layer covering the gate electrode, the gate wire, the source electrode and the source wire through a contact hole formed by boring the insulation layer, and a dummy hole is formed by boring a portion of the insulation film above at least one of the gate electrode, the gate wire, the source electrode and the source wire in close proximity to the contact hole with the dummy hole reaching the gate electrode, the gate wire, the source electrode or the source wire respectively.

Growing community of inventors

Kyoto, Japan

Hitoshi Kitagawa