Panasonic Semiconductor Solutions Co., Ltd.

Panasonic Intellectual Property Management Co., Ltd.

Nuvoton Technology Corporation Japan

Takahiro Okaguchi

Toru Takayama

Tougo Nakatani

Norio Ikedo

Tomohito Yabushita

Takeshi Yokoyama

Shinji Yoshida

Atsunori Mochida

Shoichi Takasuka

A semiconductor laser device lases in a multiple transverse mode and includes a stacked structure where a first conductivity-side semiconductor layer, an active layer, and a second conductivity-side semiconductor layer are stacked above a substrate. The second conductivity-side semiconductor layer includes a current block layer having an opening that delimits a current injection region. Side faces as a pair are formed in portions of the stacked structure that range from part of the first conductivity-side semiconductor layer to the second conductivity-side semiconductor layer. The active layer has a second width greater than a first width of the opening. The side faces in at least part of the first conductivity-side semiconductor layer are inclined to the substrate. A maximum intensity position in a light distribution of light guided in the stacked structure, in a direction of the normal to the substrate, is within the first conductivity-side semiconductor layer.

Semiconductor laser device, semiconductor laser module, and welding laser light source system

A semiconductor laser device includes: a first semiconductor layer on a first conductivity side; a second semiconductor layer on the first conductivity side; an active layer; a third semiconductor layer on a second conductivity side different from the first conductivity side; and a fourth semiconductor layer on the second conductivity side. Eg2&#x3c;Eg3 is satisfied, where Eg2 and Eg3 denote maximum values of band gap energy of the second semiconductor layer and the third semiconductor layer, respectively. The third semiconductor layer includes a first region layer in which band gap energy monotonically decreases toward the fourth semiconductor layer. N2&#x3e;N3 is satisfied, where N2 denotes an impurity concentration of the second semiconductor layer, and N3 denotes an impurity concentration of the third semiconductor layer.

Semiconductor laser device, semiconductor laser module, and laser light source system for welding

A semiconductor laser device includes: a first conductivity side semiconductor layer, an active layer; and a second conductivity side semiconductor layer. The second conductivity side semiconductor layer includes a first semiconductor layer and a second semiconductor layer, the first semiconductor layer being closer to the active layer than the second semiconductor layer is. The second semiconductor layer defines a width of a current injection region for injecting current into an optical waveguide. The current injection region includes a width varying region in which a width varies. S&#x3e;S, where Sdenotes a width of the width varying region on a front end face side, and Sdenotes a width of the width varying region on a rear end face side.

Provided is a highly reliable nitride semiconductor laser element having a robust end face protection film not being peeled even in laser operation. The nitride semiconductor laser element includes: a semiconductor multi-layer structure including a group III nitride semiconductor and having a light-emitting end face; and a protection film including a dielectric multi-layer film and covering the light-emitting end face of the semiconductor multi-layer structure. The protection film includes an end face protection layer and an oxygen diffusion suppression layer arranged sequentially in stated order from the light-emitting end face. The end face protection layer includes a crystalline film comprising nitride including aluminum. The oxygen diffusion suppression layer has a structure in which a metal oxide film is between silicon oxide films. The metal oxide film is crystallized by laser light.

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Toyama, Japan

Takahiro Okaguchi