Kabushiki Kaisha Toshiba

Hideaki Kinoshita

Naohiro Shimada

Toshiaki Tanaka

Yoshio Iizuka

Masaki Okajima

Motoyuki Yamamoto

Shozo Yuge

Hiroko Nagasaka

Gen-ichi Hatakoshi

Nobuyuki Matsuura

Hatsumi Kawata

In a semiconductor light-emitting element having a double hetero junction structure of an InGaAP system an n-type dopant, which does not change a crystal structure, is doped in an In.sub.1-y (Ga.sub.1-x Al.sub.x).sub.y P(0.ltoreq.x&lt;1, y.perspectiveto.0.5) active layer, so that an n-type active layer (4), is formed between a p-type InGaAlP cladding layer (5), which has band-gap energy that is larger than that of the active layer (4), and an n-type InGaAlP cladding layer (3), thereby preventing the dopant of the P-type InGaAlP cladding layer (3) from being dispersed into the active layer (4). Thus, the oscillation wavelength of the light-emitting element is not shifted to a short wavelength, and the threshold current of the oscillation is not increased thereby providing an element which can improve yield and reliance.

Indium gallium aluminum phosphide silicon doped to prevent zinc

A semiconductor laser including a semiconductor substrate having a high resistance region at both ends, an active layer sandwiched between two clad layers, and a window structure having both end surfaces facing each other. Each of the both end surfaces includes end portions of the active layer and the two clad layers, respectively. Since each of the end portions is disposed above the high resistance region of the semiconductor region of the semiconductor substrate, it has a band gap higher than an internal portion of the active layer and the two clad layers, respectively, thereby providing an improved window effect.

Semiconductor laser of visible ray region having window structure

A semiconductor device is disclosed in which an area pattern is formed on a portion of a major surface of a semiconductor substrate over which epitaxial growth layers are formed. In this case, compound semiconductor areas formed by an epitaxial growth method, by the utilization of a surface temperature difference between the major surface of the semiconductor surface and the area pattern in a heating process. By so doing, it is possible to simultaneously obtain the compound semiconductors of a different composition or a different energy gap from each other.

Semiconductor heterojunction device made by an epitaxial growth technique

A semiconductor laser device comprises a substrate formed of elements of the III-V groups and having one conductivity type, a lower clad layer formed on the substrate and having the same conductivity type as that of the substrate, and an upper clad layer formed on the lower clad layer and having a conductivity type opposite to that of the lower clad layer. A waveguide layer having a large refractive index is formed within the lower clad layer by decreasing the band gap of the upper clad layer. The light generated in an activation layer is guided to the lower clad layer, so as to suppress adverse effects which the upper clad layer may have on element characteristics.

Semiconductor laser device

A semiconductor light emitting device has a semiconductor light emitting element section and an n-type semiconductor substrate with a through hole which serves as a window through which light generated by the semiconductor light emitting element section is emitted. The device further includes a p-type region formed in the semiconductor substrate and facing the through hole. The p-type region and the semiconductor substrate constitute a photodiode.

Semiconductor light emitting device

A semiconductor laser diode includes two semiconductive cladding layers of different conductivity types, which are stacked on a substrate. An active layer of an undoped semiconductor film is sandwiched between the cladding layers. A channel groove is formed in a current blocking layer and the underlying cladding layer, to be deep enough to cause the current blocking layer to be divided into two parts. A waveguide layer covers the channel groove and the current-blocking layer, to provide a slab-coupled waveguide structure for transverse mode oscillation. The second cladding layer, the current-blocking layer, and the waveguide layer are composed of gallium arsenide containing aluminum.

Growing community of inventors

Yokohama, Japan

Hideaki Kinoshita