Abstract: A surface emitting semiconductor laser, with a resonator cavity transverse to the planar extent of the deposited layers, is provided with a first reflection mirror on the substrate side composed of alternating layers comprising a first layer that is made of a Group III-V compound semiconductor and a second layer that is made of a Group III-V compound semiconductor with an energy bandgap that is larger than that of the first layer. A second reflection mirror is provided at the opposite end of the cavity adjacent to a column like resonator portion. At least the first reflection mirror comprises a distributive Bragg reflection (DBR) multiple layer mirror that has an interface region between first and second layers having a carrier concentration that is higher than that of other regions. The column like resonator portion is surrounded by a buried layer which may consist of two layers, the first layer functioning as barrier layer and the second layer functioning as a flattening layer.

Abstract: A semiconductor laser comprises AlGaAs-type semiconductor layers deposited on a substrate and a current constriction layer having at least one stripe-shaped current injection region. This semiconductor layers comprise: a first cladding layer of the first conductivity type, a first optical waveguide layer of the first conductivity type formed on the first cladding layer, an active layer formed on the first optical waveguide layer and having a quantum-well structure, a second optical waveguide layer of a second conductivity type formed on the active layer, a second cladding layer of the second conductivity type formed on the second optical waveguide layer, and a contact layer formed on the second cladding layer. The active layer has flatness of such a degree that roughness with respect to a reference surface within a unit area of 1 mm.times.1 mm is no more than .+-.0.1 .mu.m, the width of the current injection region of the current constriction layer is between 100 .mu.m to 250 .mu.

Abstract: A surface emission type semiconductor laser has insulation layers (107, 108) embedding separation grooves for partially separating the waveguide path in an optical resonator formed by a pair of reflecting mirrors, namely a distributed reflection type multilayer film mirror (104) and a dielectric multilayer film mirror (111), and a quantum well active layer (105).A surface emission type semiconductor laser is designed such that the lasing wavelength .lambda..sub.G of an edge emission type semiconductor laser having the same semiconductor layers as those of the optical resonator is set to be shorter than a desired lasing wavelength .lambda..sub.EM of the surface emission type semiconductor laser by a given differential wavelength (gain offset) .DELTA..lambda..sub.EM.

Abstract: In order to manufacture a surface emission type semiconductor laser, a plurality of semiconductor layers including a multilayered semiconductor mirror, a cladding layer, an active layer and other layers are sequentially formed on a substrate through the organic metal vapor growth method. A photoresist mask is then formed on the semiconductor layers. At least the cladding layer in the semiconductor layers is anisotropically etched by the use of the photoresist mask. At least one column-like portion is thus formed to have sidewalls extending perpendicular to the substrate and to guide the light in a direction perpendicular to the substrate. Thereafter, a buried layer including a single layer formed therein at an area covering at least the sidewalls of the column-like portion is formed around the column-like portion. A multilayered dielectric mirror is deposited in the column-like portion on the light exit end thereof.

Abstract: In order to manufacture a surface emission type semiconductor laser, a plurality of semiconductor layers including a multilayered semiconductor mirror, a cladding layer, an active layer and other layers are sequentially formed on a substrate through the organic metal vapor growth method. A photoresist mask is then formed on the semiconductor layers. At least the cladding layer in the semiconductor layers is anisotropically etched by the use of the photoresist mask. At least one column-like portion is thus formed to have sidewalls extending perpendicular to the substrate and to guide the light in a direction perpendicular to the substrate. Thereafter, a buried layer including a single layer formed therein at an area covering at least the sidewalls of the column-like portion is formed around the column-like portion. A multilayered dielectric mirror is deposited in the column-like portion on the light exit end thereof.

Abstract: A surface emission type semiconductor laser includes a plurality of semiconductor layers defining at least one resonator in a direction perpendicular to the semiconductor substrate of the laser, the layers including at least a cladding layer in the semiconductor layers being formed into at least one column-like portion extending in a direction perpendicular to the semiconductor substrate, and a buried layer surrounding the column-like portion. The column-like portion is of rectangular cross-section in a plane parallel to the semiconductor substrate and having longer and shorter sides, whereby the polarization plane of said omitted laser beam is parallel to the direction of said shorter sides.

Abstract: A small and inexpensive optical head for detecting a recorded signal, a focusing error signal and a tracking error signal, and an optical memory device utilizing the optical head. A diffraction device (103) is provided having two chirped grating regions (103A, 103B) for dividing a light beam from an optical recording medium (105) and directing the divided beams toward four band-shaped photoelectric transducers (106) and an astigmatism generator formed by the diffraction device (103) and a positive lens (102). The four photoelectric transducers are positioned in a plane inclined with respect to the optical axis of zero-order diffraction light, and the longitudinal axes of each of the band-shaped photoelectric transducers are radially arranged relative to the optical axis.

Abstract: A surface emission type semiconductor laser includes a plurality of semiconductor layers defining at least one resonator in a direction perpendicular to the semiconductor substrate of the laser, the layers including at least a cladding layer in the semiconductor layers being formed into at least one column-like portion extending in a direction perpendicular to the semiconductor substrate, and a II-VI group compound semiconductor epitaxial layer buried around the column-like portions. "Lattice mismatch ratio" between the II-VI group compound semiconductor epitaxial layer and the column-like portions is no more than 0.2%, or more preferably no more than 0.16%. The II-VI group compound semiconductor layer is formed from an adduct consisting of II group organometallic compound and VI group organometallic compound and a VI group hydride by the use of a chemical vapor deposition.

Abstract: A surface emitting semiconductor laser is provided with at least reflection mirrors on the substrate side composed of a first layer that is made of a Group III-V compound semiconductor and a second layer that is made of a Group III-V compound semiconductor with an energy bandgap that is larger than that of the first layer. The first and second layers are alternately stacked. The semiconductor laser is also composed of a distributive reflection multiple layer mirror that has an interface region between first and second layers having a carrier concentration that is higher than that of other regions. As a result, the multiple layer band structure of the distributive reflection mirror has been improved, current easily flows vertically through the multiple layers and the element resistance is low.

Abstract: A surface emission type semiconductor laser includes a plurality of semiconductor layers defining at least one resonator in a direction perpendicular to the semiconductor substrate of the laser, the layers including at least a cladding layer in the semiconductor layers being formed into at least one column-like semiconductor layer extending in a direction perpendicular to the semiconductor substrate, and a II-VI group compound semiconductor epitaxial layer buried around the at least one column-like semiconductor layer. If a plurality of column-like semiconductor layers are to be formed by a separation groove, these column-like semiconductor layers are separated from one another, the II-VI group compound semiconductor epitaxial layer being buried in the separation groove.

Abstract: A surface emission type semiconductor laser includes a plurality of semiconductor layers defining at least one resonator in a direction perpendicular to the semiconductor substrate of the laser, the layers including at least a cladding layer in the semiconductor layers being formed into at least one column-like portion extending in a direction perpendicular to the semiconductor substrate, and a II-VI group compound semiconductor epitaxial layer buried around the column-like portions. The II-VI group compound semiconductor layer is formed from an adduct consisting of II group organometallic compound and VI group organometallic compound and a VI group hydride by the use of a chemical vapor deposition. If a plurality of column-like portions are to be formed by a separation groove, these column-like portions are separated from one another, the II-VI group compound semiconductor epitaxial layer being buried in the separation groove.

Abstract: A surface emission type semiconductor laser includes a plurality of semiconductor layers defining at least one resonator in a direction perpendicular to the semiconductor substrate of the laser, the layers including at least a cladding layer in the semiconductor layers being formed into at least one column-like portion extending in a direction perpendicular to the semiconductor substrate, and a II-VI group compound semiconductor epitaxial layer buried around the column-like portion. The column-like portion is of rectangular cross-section in a plane parallel to the semiconductor substrate and having longer and shorter sides, whereby the polarization plane of said emitted laser beam is parallel to the direction of said shorter sides.

Abstract: A microwave ECR plasma etching method and apparatus employs a combination reactive gas medium supplied to a microwave excitation ECR plasma chamber coupled to a treatment chamber containing a Group II-VI sample to be etched. A reactive gas plasma is formed containing reactive species in the plasma chamber and the Group II-VI sample is irradiated with a beam of reactive species formed from the reactive gas plasma. The reactive gas medium is selected from the group consisting of a hydrogen halogenate, a mixture of a halogen gas and an inert gas, a mixture of a halogen gas and hydrogen gas, a mixture of a halogen gas, an inert gas and hydrogen gas, and a mixture of a halogen gas and nitrogen gas.

Abstract: A surface emission type semiconductor laser includes a plurality of semiconductor layers defining at least one resonator in a direction perpendicular to the semiconductor substrate of the laser, the layers including at least a cladding layer in the semiconductor layers being formed into at least one column-like semiconductor layer extending in a direction perpendicular to the semiconductor substrate, and a II-VI group compound semiconductor epitaxial layer buried around the at least one column-like semiconductor layer. If a plurality of column-like semiconductor layers are to be formed by a separation groove, these column-like semiconductor layers are separated from one another, the II-VI group compound semiconductor epitaxial layer being buried in the separation groove.

Abstract: A surface emission type semiconductor laser includes a plurality of semiconductor layers defining at least one resonator in a direction perpendicular to the semiconductor substrate of the laser, the layers including at least a cladding layer in the semiconductor layers being formed into at least one column-like light emitting portion extending in a direction perpendicular to the semiconductor substrate, and a II-VI group compound semiconductor epitaxial layer buried around the column-like portion. An active layer of multi-quantum well structure is further formed on the layer section of the cladding layer having the column-like portion. If a plurality of column-like portions are formed, these column-like portions are separated from one another by a separation groove terminating short of the active layer, the II-VI group compound semiconductor epitaxial layer being buried in the separation groove.

Abstract: A surface emission type semiconductor laser includes a plurality of semiconductor layers defining at least one resonator in a direction perpendicular to the semiconductor substrate of the laser, at least a cladding layer in the semiconductor layers being formed into at least one column-like semiconductor layer extending in a direction perpendicular to the semiconductor substrate, and a II-VI group compound semiconductor epitaxial layer buried around the column-like semiconductor layer. The semiconductor laser also includes an exit-side electrode which is formed in contact with a contact layer of the column-like semiconductor layer which has an opening used to form an exit port. The opening is formed in the exit-side electrode at a position including the geometric center of the contact layer and ranging between 10% and 90% of the surface area of the contact layer.

Abstract: A quite small device producing blue light with small loss of light. The device has a laminated laser light-emitting portion and an optical waveguide for second-harmonic generation. Both light-emitting portion and waveguide are formed on the same semiconductor substrate. The waveguide takes the form of a thin laminated layer. The laser light-emitting portion and the waveguide are substantially flush with each other.

Abstract: A laser has an active layer formed on a prepared substrate, a cladding layer on the active layer and a contact layer on the cladding layer. The active layer and contact layer are formed of a semiconductor material of elements from Groups III-V. The contact layer and cladding layer are formed into an elongated projecting rib wherein the cladding layer has a remaining planar portion disposed across the active layer. An insulating layer of semiconductor of elements from Group II-VI is formed on each side of the rib supported on the remaining cladding layer.

Abstract: The invention relates to improvements in an electrophotographic sensitive member having a photoconductive layer formed with amorphous silicon produced by glow discharge decomposition or sputtering. An electrophotographic sensitive member is formed by laminating an amorphous silicon barrier layer and an amorphous photoconductive layer successively on an electrically conductive substrate, the first mentioned layer containing an impurity of Group IIIa of Periodic Table of Elements, or nitrogen and impurity of Group IIIa of same Table, and also containing oxygen within a range of 0.1 to 20.0 atomic % at the point of the layer and in a progressively decreasing pattern throughout the rest thereof. Constructed as such, the photosensitive member has an increased photosensitivity to near-infrared beams, a large charge-holding capability, and low-rate dark attenuation characteristics. In addition, it is less expensive to manufacture.

Abstract: The invention relates to improvements in an electrophotographic sensitive member having a photoconductive layer formed with amorphous silicon produced by glow discharge decomposition or sputtering. An electrophotographic sensitive member is formed by laminating an amorphous silicon barrier layer and an amorphous photoconductive layer successively on an electrically conductive substrate, the first mentioned layer containing an impurity of Group IIIa of Periodic Table of Elements, or nitrogen and impurity of Group IIIa of same Table, and also containing oxygen within a range of 0.1 to 20.0 atomic % at the point of the layer and in a progressively decreasing pattern throughout the rest thereof. Constructed as such, the photosensitive member has an increased photosensitivity to near-infrared beams, a large charge-holding capability, and low-rate dark attenuation characteristics. In addition, it is less expensive to manufacture.