Sumitomo Electric Industries, Limited

Nobuyuki Ikoma

Takahiko Kawahara

Jun-ichi Hashimoto

Masayuki Shigematsu

So Tanaka

Tsukuru Katsuyama

Akihiro Moto

Kenji Hiratsuka

Michio Murata

Mitsuo Takahashi

Tatsuya Tanabe

Manabu Yoshimura

Jiro Fukui

Shigenori Takagishi

Akira Ishida

In a method of fabricating a semiconductor optical device, a semiconductor region is formed by growing an InP lower film, a active region, an InP upper film and a capping film on a substrate sequentially. Material of the capping film is different from that of InP. Next, a mask is formed on the capping film, and the semiconductor region is etched using the mask to form a semiconductor stripe mesa, which includes an InP lower cladding layer, a active layer, an InP upper cladding layer and a capping layer. The active layer comprises aluminum-based III-V compound. A width of the top surface of the capping layer is greater than that of a width of the bottom surface of the capping layer. A width of the top surface of the InP upper cladding layer is smaller than that of the bottom surface of the InP upper cladding layer. The minimum width of the semiconductor mesa is in the InP upper cladding layer. After forming the semiconductor stripe mesa, thermal process of the semiconductor mesa is carried out in an atmosphere to form a mass transport semiconductor on a side of the InP upper cladding layer, and the atmosphere contains V-group material.

Semiconductor optical device and method of fabricating the same

The present invention is to provide a semiconductor laser with a feedback grating comprised of InP and AlGaInAs without InAsP put therebetween, and to provide a method for manufacturing the DFB-LD having such grating. The LD includes an n-type InP substrate, an AlInAsP intermediate layer, an AlGaInAs lower SCH layer, an active layer, and a p-type layer for upper cladding in this order from the InP substrate. The InP substrate, the AlInAsP intermediate layer, and the AlGaInAs lower SCH layer constitute the feedback grating. The AlInAsP intermediate layer lowers a series resistance along these semiconductor stacks.

Semiconductor laser and the method for manufacturing the same

The semiconductor optical device is provided with an optical waveguide part and an optical amplification part respectively provided on the GaAs semiconductor substrate. The optical amplification part includes at least one semiconductor optical amplifier. The optical waveguide part includes optical elements including optical waveguides. The optical waveguides are optically connected to the semiconductor optical amplifier. The semiconductor optical amplifier is provided with an active layer including a Ga In N As semiconductor, a first conductive type clad layer and a second conductive type clad layer respectively with the active layer between them. The optical waveguides are respectively provided with a core semiconductor layer including at least either of a GaInNAs semiconductor or a GaAs semiconductor, a first clad semiconductor layer and a second clad semiconductor layer respectively with the core semiconductor layer between them.

Semiconductor optical device and method of manufacturing the same

A semiconductor layer consisting of Ga.sub.1-x In.sub.x N.sub.y As.sub.1-y and/or GaN.sub.y As.sub.1-y and formed by incorporating nitrogen into a group III-V mixed crystal semiconductor is provided on a GaAs substrate. The hydrogen concentration in the semiconductor is kept at 5.times.10.sup.18 atoms/cm.sup.3 or below.

Method of crystal growth of compound semiconductor, compound

In the present method, at the time when a semiconductor laser is being made, nitrogen or phosphorus element is introduced into an active layer comprising a GaAs based compound from an end face thereof, thereby changing the region of the active layer in the vicinity of the end face into a GaN or GaP based compound. Accordingly, the energy band gap of this region is made wider than the energy band gap within the active layer, and thus substituted region is changed into a layer transparent to the laser light generated within the active layer. Thus, the end face can be prevented from deteriorating upon the temperature rise caused by laser light absorption at the end face.

Semiconductor laser and method of making the same

The present invention relates to a semiconductor laser equipped with a novel window structure, thereby realizing higher output, and a method of making the same. The method is a method of making a semiconductor laser having a window structure transparent to emitted laser light. In particular, into a laminate structure comprising a semiconductor substrate, a lower cladding layer, an active layer, and an upper cladding layer, impurity atoms is implanted to a predetermined region of the upper cladding layer by ion implantation method, thereby forming an impurity implanted region above the active layer. Further, in this method, after the laminate structure is heat-treated to such an extent that the impurity atom fails to reach the active layer, the laminate structure is cleaved in the area where the impurity atom is implanted, thus yielding a semiconductor laser. As a result of such a heat treatment, the vacancies generated upon ion implantation diffuse into the active layer, whereas the impurity atoms themselves do not diffuse into the active layer. This vacancy diffusion forms, in the vicinity of the cleavage plane in the active layer, a window structure in which a well layer and barrier layers which constitute the quantum well structure are selectively interdiffused. This window structure suppresses the catastrophic optical damage during high output operation.

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Yokohama, Japan

Nobuyuki Ikoma