Sharp Kabushiki Kaisha Corporation

501 Sharp Kabushiki Kaisha

Sadayoshi Matsui

Mototaka Taneya

Mitsuhiro Matsumoto

Haruhisa Takiguchi

Shinji Kaneiwa

Toshihiko Yoshida

Hiroyuki Hosoba

Saburo Yamamoto

Takahiro Suyama

Seiki Yano

Hiroaki Kudo

Taiji Morimoto

Hidenori Kawanishi

Hiroshi Hayashi

Osamu Yamamoto

Kosei Takahashi

Toshio Hata

Masafumi Kondo

Akinori Seki

Nobuyuki Miyauchi

Atsuo Tsunoda

Masahiro Hosoda

Toshiro Hayakawa

Kazuaki Sasaki

Masaki Kondo

Toshimasa Hamada

Tadashi Takeoka

Masumi Nakamichi

Masahiro Yamaguchi

Shohichi Kato

Masafumi Kondou

A semiconductor fabrication apparatus for evaporating a material in a growth chamber by a molecular beam epitaxy technique to fabricate a semiconductor is provided. The apparatus includes: an ultra-high vacuum chamber including a liquid nitrogen cold trap therein, the ultra-high vacuum chamber being connected to the growth chamber via a valve; a first evacuation system including an ultra-high vacuum evacuation system, the first evacuation system being connected to the ultra-high vacuum chamber; and a second evacuation system including an evacuation system capable of conducting an evacuation operation even in a low vacuum condition, the second evacuation system being connected to the liquid nitrogen cold trap. The first evacuation system and the second evacuation system independently conduct the respective evacuation operations.

Method and apparatus for fabricating semiconductor

In an AlGaInP type semiconductor light-emitting device, an n-type AlGaInP cladding layer and a p-type AlGaInP cladding layer are deposited so as to interpose an active layer made of GaInP or AlGaInP therebetween. Light guiding layers are provided between the active layer and the n-type cladding layer, and/or, between the active layer and the p-type cladding layer, respectively. The p-type cladding layer is doped with Be serving as a p-type dopant. The active layer, the p-type cladding layer and the light guiding layers are doped with Si which may serve as an n-type dopant.

Semiconductor light-emitting device

A method for growing a compound semiconductor layer of Al.sub.x Ga.sub.1-x As (0.ltoreq.x.ltoreq.1) on a compound semiconductor substrate uses a molecular beam epitaxial apparatus, the method including the steps of providing the substrate having a GaAs layer on an upper surface thereof, thermally etching the GaAs layer by heating the substrate at a temperature and irradiating the GaAs layer with a gallium molecular beam and an arsenic molecular beam to expose the upper surface of the substrate, and growing the Al.sub.x Ga.sub.1-x As (0.ltoreq.x.ltoreq.1) layer on the upper surface of the substrate.

Method for growing a compound semiconductor and a method for producing a

A hyper-resolution optical device which can focus a beam of light to a diameter less than the diffraction limit. The optical device has an optical system disposed on a transmissive substrate. One component in the optical system is a hyper-resolution optical component which passes or reflects light and which has a central portion which does not pass or reflect light, respectively. The hyper-resolution optical component can be integrated with the transmissive substrate. Such optical devices are particularly suitable for optical pick-up devices, laser printers, sensors.

Hyperresolution optical system

On a GaAs substrate (Al.sub.Y Ga.sub.1-Y).sub.0.5 In.sub.0.5 P crystal layers (0.ltoreq.Y.ltoreq.1) is formed to be lattice-matched with the substrate. By radiating As molecular beams on the surface of the crystal layers while heating the layered substrate to a temperature at which In in the crystal layers evaporates, the portion near the surface of the crystal layers is changed into an Al.sub.Y Ga.sub.1-Y As crystal layer (0.ltoreq.Y.ltoreq.1) of a thickness of several molecules, on which layer an Al.sub.X Ga.sub.1-X As crystal layer (0.ltoreq.X.ltoreq.1) is formed. Since the surface of the Al.sub.Y Ga.sub.1-Y As crystal layer has been purl fled, the formed Al.sub.X Ga.sub.1-X As crystal layer has a high crystallinity, allowing production of a light emitting diode, a semiconductor laser device and the like with high efficiency.

Semiconductor laser device, and a method for producing a compound

A semiconductor laser device which can effectively confine electrons and positive holes is disclosed. The semiconductor laser device includes a semiconductor substrate of a first conductivity type, a current blocking layer of a second conductivity type, a first semiconductor layer of the first conductivity type made of a III-V group compound semiconductor, an active layer made of a III-V group compound semiconductor, and a second semiconductor layer. The semiconductor substrate has a ridge-type mesa having (n11)A planes. The current blocking layer is formed on the semiconductor substrate other than the top face of the mesa. The first semiconductor layer is formed on the entire surface of the current blocking layer and on the top face of the mesa. The active layer is formed on the first semiconductor layer. The second semiconductor layer is formed on the active layer. The second semiconductor layer has inclined portions, and is made of a III-V group compound semiconductor containing an amphoteric element as an impurity so that the inclined portions are of the first conductivity type and the other portions are of the second conductivity type.

Semiconductor laser device

On a GaAs substrate (Al.sub.Y Ga.sub.1-Y).sub.0.5 In.sub.0.5 P crystal layers (0.ltoreq.Y.ltoreq.1) is formed to be lattice-matched with the substrate. By radiating As molecular beams on the surface of the crystal layers while heating the layered substrate to a temperature at which In in the crystal layers evaporates, the portion near the surface of the crystal layers is changed into an Al.sub.Y Ga.sub.1-Y As crystal layer (0.ltoreq.Y.ltoreq.1) of a thickness of several molecules, on which layer an Al.sub.X Ga.sub.1-X As crystal layer (0.ltoreq.X.ltoreq.1) is formed. Since the surface of the Al.sub.Y Ga.sub.1-Y As crystal layer has been purified, the formed Al.sub.X Ga.sub.1-X As crystal layer has a high crystallinity, allowing production of a light emitting diode, a semiconductor laser device and the like with high efficiency.

A semiconductor laser device is disclosed which comprises a semiconductor substrate having a ridge portion, the width of the ridge portion being smaller in the vicinity of the facets than in the inside of the device; a current blocking layer formed on the substrate including the ridge portion; at least one striped groove formed on the center of the ridge portion through the current blocking layer; and a multi-layered structure disposed on the current blocking layer, the multi-layered structure successively having a first current blocking layer, an active layer for laser oscillation, and a second current blocking layer; wherein at least two side grooves are symmetrically formed on both sides of the center region of the ridge portion with the same width as that of the regions thereof near the facets. Also, disclosed is a method for producing the semiconductor laser device.

A semiconductor laser device is provided which includes a semiconductor substrate and a multi-layered structure disposed on the substrate, the multi-layered structure containing an Al.sub.x Ga.sub.1-x As (0&lt;x&lt;1) first cladding layer formed on the substrate, an Al.sub.y Ga.sub.1-y As (0&lt;y&lt;1, x&gt;y) active layer for laser oscillation formed on the first cladding layer, an Al.sub.x Ga.sub.1-x As (0&lt;x&lt;1) second cladding layer formed on the active layer, and an Al.sub.z Ga.sub.1-z As (0&lt;z&lt;1) current blocking layer formed above the second cladding layer, the current blocking layer having a striped groove as a current injection path. The method includes the steps of: forming a multi-layered structure on a semiconductor substrate, the multi-layered structure containing in order, an Al.sub.x Ga.sub.1-x As (0&lt;x&lt;1) first cladding layer, an Al.sub.y Ga.sub.1-y As (0&lt;y&lt;1, x&gt;y) active layer for laser oscillation, an AlGaAs (0&lt;x&lt;1) second cladding layer, a GaAs buffer layer, an Al.sub.u Ga.sub.1-u As (0&lt;u&lt;1) etching stopper layer, an Al.sub.z Ga.sub.1-z As (0&lt;z&lt;1, z&lt;u) current blocking layer, and a GaAs protective layer; etching the protective layer and the current blocking layer to form a striped groove as a current injection path; removing the exposed portion of the etching stopper layer on the bottom of the striped groove; removing the portion of the buffer layer on the bottom of the striped groove and at least one part of the protective layer by a melt-back technique; and growing an Al.sub.x Ga.sub.1-x As (0&lt;x&lt;1) third cladding layer so as to bury the striped groove therein and growing a GaAs contact layer on the third cladding layer.

Semiconductor laser device and a method of fabricating the same

A semiconductor laser device and a method for the production of the semiconductor laser device are provided, which semiconductor laser device includes a striped channel formed in a semiconductor substrate through a current blocking layer on the substrate and at least two dummy grooves formed in the current blocking layer on each side of the striped channel. Also provided are a semiconductor wafer prepared for the purpose of producing optical devices with an optical waveguide, and a method for the production of the semiconductor wafer. The semiconductor wafer includes a semiconductor substrate, the surface of which has an orientation inclined from the [100] direction to one of the [011] and [011] directions of an angle .theta. satisfying the relationship 0.1.degree.&lt;.vertline..theta..vertline.&lt;4.degree.; a plurality of striped channels formed in a substrate through a current blocking layer in the direction of the other of the [011] and [011] directions; and at least one dummy side groove formed between the striped channels, having a combined cross-sectional area on the plane perpendicular to the other direction greater than that of each of the striped channels.

Semiconductor laser device, a semiconductor wafer

A method for the formation of a diffraction grating on a substrate using a holographic technique and an etching technique, wherein the periodicity of the pattern of the diffraction grating can be changed at will by a change of the light-path length of one of the two light fluxes from a holographic exposing system.

Method for the formation of a diffraction grating

A scanning apparatus with a refracting function comprising a laser beam oscillating area, one or more refracting areas with a waveguide having different refractive indexes, wherein an electric field is applied to the waveguide of the refracting area, by which the changes in the refractive index of the waveguide of the refracting area are attained so that laser beams from the laser beam oscillating area undergo refraction while they pass through the waveguide of the refracting area.

Scanning apparatus with refracting area of variable refractive index

A semiconductor laser array apparatus comprising a single substrate and a plurality of semiconductor laser devices that are disposed with a given pitch on the substrate, some of the semiconductor laser devices constituting laser devices of a laser oscillation-operating area of the semiconductor laser array apparatus and the other semiconductor laser devices constituting laser devices of the non-laser oscillation-operating areas that are positioned outside of the laser oscillation-operating area, wherein the oscillation threshold current level of at least one of the semiconductor laser devices of each of the non-laser oscillation-operating areas that is the closest to the laser oscillation-operating area is higher than those of the semiconductor laser devices of the laser oscillation-operating area.

Semiconductor laser array apparatus

A buried type semiconductor laser device comprising a multi-layered epitaxial growth crystal including a striped laser-oscillation operating area on a semiconductor substrate, wherein said laser-oscillation operating area contains a buffer layer having the same polarity as said substrate, an active layer and a cladding layer having a polarity different from that of said substrate, said laser-oscillation operating area being sandwiched between one part of the burying layer and another part of the burying layer, which are disposed on said substrate and which have a polarity different from that of said substrate, through said substrate or a diffusion region having an impurity with the same polarity as said substrate so as to electrically isolate said burying layer from said cladding layer, thereby maintaining ineffective current flowing from said cladding layer to said burying layer at a low level even when current injected into said device is increased.

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Tenri, Japan

Sadayoshi Matsui