公开(公告)号：JP2000068608A

公开(公告)日：2000-03-03

申请号：JP23684898

申请日：1998-08-24

Applicant: AGENCY IND SCIENCE TECHN

Inventor： SHIMIZU MITSUTOSHI ,  OKUMURA HAJIME ,  SHIRAKASHI JUNICHI ,  WATANABE MASANOBU

IPC: H01L21/308 ,  H01L33/32 ,  H01S5/00 ,  H01S5/323 ,  H01L33/00

Abstract: PROBLEM TO BE SOLVED: To enable wet etching with little damage by etching chemically stable gallium nitride using reactive pyrophosphoric acid. SOLUTION: A gallium nitride growing substrate, a holding device or the like are pre-heated to the same temperature as an etching temperature. Then the gallium nitride growing substrate is soaked in pyrophosphoric acid to be etched. Optimum time to soak should be calculated by pre-conditioning. A temperature of pyrophosphoric acid should be also calculated similarly. Pyrophosphoric acid can be obtained by dehydrating orthophosphoric acid which is usually used. Or it can be obtained by adding water of a suitable ratio to phosphorus oxide. In addition, sufficient etching speed can be obtained by raising the temperature of the pyrophosphoric acid to a high temperature ranging from 210 to 220 deg.C or higher. Then after the time required for etching, materials are taken out, and the pyrophosphoric acid remaining on surfaces is removed using pure water.

公开(公告)号：JP2000338453A

公开(公告)日：2000-12-08

申请号：JP14717099

申请日：1999-05-26

Applicant: AGENCY IND SCIENCE TECHN ,  SHIMIZU MITSUTOSHI

Inventor： SHIMIZU MITSUTOSHI ,  SUZUKI KATSUHIRO

IPC: G02F1/015 ,  G02B6/12 ,  G02F1/01 ,  G02F1/35 ,  H01S5/00 ,  H01S5/026 ,  H01S5/042 ,  H01S5/06 ,  H01S5/12 ,  H01S5/16 ,  H01S5/50 ,  G02F1/017

Abstract: PROBLEM TO BE SOLVED: To enable miniaturization and the simpler manufacture thereof by alternately arraying >=2 pairs of saturable amplification regions and saturable absorber regions in series. SOLUTION: The width of light pulses is compressed by using a semiconductor optical waveguide structure of a structure obtained by alternately lining up the gain regions 1 and the saturable absorption regions (saturable absorbers) 2. Namely, the effect of narrowing the pulse width is effected by the saturable absorption regions 2 and the role of restoring the energy (light) quantity over the entire part attenuated by the absorption is born by the gain regions 1. When the absorption is continued without the execution of amplification, the light pulses attenuate and, therefore, the element is provided with the gain regions by each of the respective stages, by which the light pulses are amplified. If the paired saturable absorption regions 2 and the gain regions 1 are alternately arranged in this order and the light pulses are passed therethrough, the pulse widths are narrowed by each of the respective stages. The light pulses are introduced and passed into the alternately lined up light pulse compression regions, by which the light pulses are effectively compressed.

公开(公告)号：JPH11233889A

公开(公告)日：1999-08-27

申请号：JP2938098

申请日：1998-02-12

Applicant: AGENCY IND SCIENCE TECHN

Inventor： SHIMIZU MITSUTOSHI

IPC: H01S3/10 ,  H01S5/00 ,  H01S5/042 ,  H01S5/183 ,  H01S5/50 ,  H01S3/18

Abstract: PROBLEM TO BE SOLVED: To provide an optical element which can produce light easily in high volume with high precision by making the element in such a structure that a light amplifying function section is attached to a transparent supporting substrate and light is made incident to an active layer through the transparent supporting substrate and light beam is emitted from the active layer. SOLUTION: A light amplifying function section 11 having such a structure that an active layer 13 for generating exciting carriers is put from up and down by a p-type and an n-type semiconductor layer 14, 12 is attached with a transparent adhesive 22 to a transparent substrate 21 which is different from a substrate on which the light amplifying function section 11 is built. Light beam generated in the active layer 13 is reflected on a reflecting mirror 14 and is radiated into an outside space from an n-type clad layer 12 through the transparent substrate 21. By locating a flat-type dielectric multilayer film reflecting mirror on the extension line of a light beam emission path in the outside space, an outside reflecting mirror-type surface emission laser can be formed in a complete form. For the active layer 13 to generate exciting carriers, current needs to be injected into the active layer 13. In this case, current is injected by means of a divided electrode 16 for injecting holes which have been divided into a plurality of electrodes.

公开(公告)号：JPH11186535A

公开(公告)日：1999-07-09

申请号：JP34761297

申请日：1997-12-17

Applicant: AGENCY IND SCIENCE TECHN

Inventor： SHIMIZU MITSUTOSHI ,  OGURA MUTSURO ,  KAJI RYOSAKU ,  NAKAGAWA ITARU ,  MUKAI SEIJI

IPC: H01L29/68 ,  H01L29/06 ,  H01L29/66 ,  H01L29/86

Abstract: PROBLEM TO BE SOLVED: To provide a semiconductor device capable of operating at a high speed with negative characteristics. SOLUTION: A main current path (a main electron path comprises a quantum wire 13, and an electron injection region 13E and an electron extracting region 13C are formed separately each other on the quantum wire 13 in its lengthwise direction. A multiple quantum barrier region 13M, selectively formed by an externally impressed field and not by metallurgically, is formed between these region. A control region or a region accelerating electron 13B is formed between the multiple quantum barrier region 13M and the electron injection region 13E. The respective electrodes, 15, 16, 18, and 17 are formed in respective regions 13E, 13B, 13M, and 13C via a thin barrier layer layer 14.