Matsushita Electric Industrial Co., Ltd.

Matsushita Electronics Corporation

Hirokazu Shimizu

Kunio Itoh

Masaru Wada

Takashi Sugino

Masahiro Kume

Ken Hamada

Hideyuki Nakanishi

Toru Takayama

Akio Yoshikawa

Iwao Teramoto

Hiroki Naito

Kazuo Fujimoto

Hideyuki Sugiura

Takao Shibutani

Issei Ohta

Daisuke Ueda

Masaaki Yuri

Masahiro Ishida

Masahiro Ogawa

Shinichi Takigawa

Kunio Ito

Hiroyuki Mizuno

Takako Okabe

Masuru Wada

Issei Ota

Fumiko Tajiri

Hiroki Naitou

A first semiconductor layer is formed on a mother substrate, and the mother substrate is irradiated with irradiation light from a surface opposite to the first semiconductor layer, so that a thermally decomposed layer formed by thermally decomposing the first semiconductor layer between the first semiconductor layer and the mother substrate. Then, a second semiconductor layer including an active layer is formed on the first semiconductor layer in which the thermally decomposed layer is formed.

Method for producing a semiconductor device

Radiating light from a semiconductor laser element is radiated in a direction normal to the surface of a photodetector substrate. The semiconductor laser element and photodetector are disposed on the same plane. Specifically, a reflecting mirror surface formed of a slanting surface of (111) lattice plane having a ridge line of &lt;110&gt; direction is disposed on a silicon substrate of (100) lattice plane having an off-angle of 4.degree. to 14.degree. about an axis of &lt;110&gt; direction or on a silicon substrate of (511) lattice plane having an off-angle of 1.degree. to 11.degree. about an axis of &lt;110&gt; direction. The semiconductor laser chip is disposed at a position opposing to the reflecting mirror surface.

Semiconductor laser device

A semiconductor laser device of low operating current and low noise for the 780 nm band to be used as the light source for an optical disc and its fabrication method. The device comprises: a certain conduction type Ga.sub.1-Y1 Al.sub.Y1 As first light guide layer, a Ga.sub.1-Y2 Al.sub.Y2 As second light guide layer of said certain conduction type, or an In.sub.0.5 Ga.sub.0.5 P or an In.sub.0.5 (GaAl).sub.0.5 P or an InGaAsP second light guide layer, successively formed one upon another at least in one side of the principal plane of an active layer; an opposite conduction type Ga.sub.1-Z Al.sub.Z As current blocking layer formed on the second light guide layer and provided with a stripe-like window; and a Ga.sub.1-Y3 Al.sub.Y3 As cladding layer of the same conduction type a said light guide layers formed on said stripe-like window, wherein relations of Z&gt;Y3&gt;Y2 and Y1&gt;Y2 are established among Y1, Y2 Y3 and Z that define the AlAs mole-fractions.

Semiconductor laser device fabrication method

Semiconductor laser device with integrated reflector on a (511) tilted

A deflection plate for deflecting laser beams includes a transparent plate on which two grating areas are formed on the same surface. The first grating area has a plurality of parallel grooves. The second grating area has a plurality of grooves in a predetermined pattern. The depth and/or the duty ratio of the grooves in the first grating area differs from that in the second grating area.

Deflection plate for optical pick-up device

A semiconductor laser device suitable as a light source for an optical disk may be operated at a low operating current with low noise for the 780 nm band. The device comprises: a certain conduction type Ga.sub.1-Y1 Al.sub.Y1 As first light guide layer, a Ga.sub.1-Y2 Al.sub.Y2 As second light guide layer of said certain conduction type, or an In.sub.0.5 Ga.sub.0.5 P or an In.sub.0.5 (GaAl).sub.0.5 P or an InGaAsP second light guide layer, successively formed one upon another at least in one side of the principal plane of an active layer; an opposite conduction type Ga.sub.1-Z Al.sub.Z As current blocking layer formed on the second light guide layer and provided with a stripe-like window; and a Ga.sub.1-Y3 Al.sub.Y3 As cladding layer of the same conduction type as the light guide layers formed on the stripe-like window. The relations of Z&gt;Y3&gt;Y2 and Y1&gt;Y2 define the AlAs mole fractions.

Low operating current and low noise semiconductor laser device for

In a semiconductor laser device, a Ga.sub.1-y Al.sub.y As cladding layer of a conduction type is provided on at least one principal plane of an active layer, while a Ga.sub.1-Z Al.sub.Z As current blocking layer of the other conduction type is provided on the cladding layer and has a stripe-like window. The AlAs mode fractions Y and Z has a relation, Z&gt;Y. The semiconductor laser device has low noises and a low operating current value.

Semiconductor laser device including a gallium-aluminum arsenic compound

A semiconductive laser device having a resonator which is formed with a dielectric film on at least one end face thereof is described. The dielectric film is in a thickness of at least three times a wavelength in the dielectric film by which the oscillation wavelength becomes very stable.

A BTRS (buried Twin-Ridge Substrate) structure laser, wherein an oblong protrusion (10) is provided on a substrate (1) of a first conductivity type and two ridges (9, 9) divided by a groove (31) therebetween are provided on a second layer (2) of a second conductivity type, and thereon plural layers (3, 4, 5, 6) including an active layer (4) are provided is improved to have longer service life such that: the protrusion (10) is shortened so as to have its both ends apart inside cavity facet of the substrate (1), or further by width of each ridge (9, 9) is narrowed at both ends thereof thereby forming narrowed end parts (9', 9'), so that excessive current injection to the active layer near the cavity facet is eliminated.

Buried twin ridge substrate laser

In a TRS (twin ridge substrate) type semiconductor laser, reflectivity at both facets of the resonator at the oscillation wavelength is selected to be higher than the reflectivity of the semiconductor crystal of the laser device, but smaller than 1, thereby stabilizing the light oscillation with a low S/N ratio.

Semiconductor laser device with decreased light intensity noise

The invention provides a chemical etching method for a semiconductor device, which comprises a step of forming a first layer of Ga.sub.1-x Al.sub.x As (0.ltoreq.x&lt;1) having a surface (100), a step of forming on the first layer a second layer of Ga.sub.1-y Al.sub.y As (0.ltoreq.y&lt;1) having a surface (100), and a step of chemically etching the layers from a level above the second layer and along the direction of &lt;011&gt;. The slope angle of etch face of the second layer depends on the mol fraction y of the second layer, and the slope angle of etch face of the first layer depends on the mol fraction y of the second layer and the mol fraction x of the first layer. These facts are best utilized in the invention so that the etch profile of the first layer may have a desired slope angle. By utilizing this chemical etching method it is possible to produce by chemical etching a semiconductor laser having a flat cavity facet perpendicular to a junction; it is also possible to provide an inner stripe type semiconductor laser having grooves whose side walls are perpendicular.

Method of manufacturing semiconductor device

In a laser of such type that the distribution of the effective refractive index varies in a direction which is along the face of its active layer and perpendicular to the direction of the laser light transmission, thereby defining the active region to be between a pair of refractive index changing zones, the refractive indexes of a pair of end surfaces of a laser resonator (i.e. the active region) is made smaller than the intrinsic refractive indexes of the cleavage face of the active layer.

Semiconductor laser

A mounting of semiconductor laser chip on a heat sink or metal mount is improved so as to enable high accuracy of position and direction. A heat sink or metal mount, on which a semiconductor laser chip is mounted, comprises two parts, namely a main mount or larger portion and a sub-mount or smaller portion. The semiconductor laser chip is soldered by a solder layer on the sub-mount utilizing a microscope so as to assure an accurate position and an accurate direction with respect to the sub-mount. Then, the sub-mount is soldered on the main mount by a solder layer with an accurate relation both in position and direction by engaging a linear ridge as a first engaging means provided on the upper face of the main mount with a straight groove and a rear end face as a second engaging means. As a result of the above-mentioned structure, accurate position and direction of the semiconductor laser chip with respect to the mount is easily obtainable with a high yield.

Semiconductor laser structure including dual mounts having ridge and

A mounting of semiconductor laser chip on a heat sink or metal mount is improved so as to enable high accuracy of position and direction. A heat sink or metal mount, on which a semiconductor laser chip is mounted, comprises two parts, namely a main mount or larger portion and a sub-mount or smaller portion. The semiconductor laser chip is soldered by a solder layer on the sub-mount utilizing a microscope so as to assure an accurate position and an accurate direction with respect to the sub-mount. Then, the sub-mount is soldered on the main mount by a solder layer with an accurate relation both in position and direction by engaging a linear ridge as a first engaging means provided on the upper face of the main mount with a straight groove and a rear end face as a second engaging means, or by engaging a square recess as a first engaging means and the square bottom of the sub-mount as a second engaging means with each other. As a result of the above-mentioned structure, accurate position and direction of the semiconductor laser chip with respect to the mount is easily obtainable with a high yield.

On a semiconductor laser substrate, a groove of tapered width is formed, and at least one crystal layer is formed on the substrate. The crystal layer is usable as a waveguide with two light input ends l.sub.1 and l.sub.2 and one light output end l.sub.3 as shown in FIG. 4(C).

Growing community of inventors

Toyonaka, Japan

Hirokazu Shimizu