Nec Corporation

Isao Yoneda

Junichi Sasaki

Hiroshi Honmou

Masataka Itoh

Kiyoshi Fukushima

An array type laser diode includes an active layer, a cathode electrode, and bonding electrodes. The active layer is formed in a substrate into a stripe shape to serve as an emission portion. The cathode electrode is formed on a mounting surface of the substrate into a stripe shape to be close to the active layer. The bonding electrodes are formed on the mounting surface of the substrate to be physically separated from the drive electrode.

Array type laser diode

It is an object of the invention to effectively use semiconductor laser elements by suppressing difficulties caused by heat generated at the times of mounting and light emission in the semiconductor laser elements. A semiconductor laser module comprises a light source-mounting section, on which plural semiconductor laser elements are mounted and optical fiber-fixing section, which upports plural optical fibers at a predetermined lateral pitch. A pitch-converting section is provided between the light source-mounting section and the optical fiber-fixing section in order to respectively guide lights semitted from the semiconductor laser elements to the corresponding optical fibers. The light source-mounting section, the pitch-converting section and the optical fiber fixing section are formed on the same substrate.

Pitch-converting substrate used in semiconductor lasermodule and

A single-type array optical conversion apparatus includes a substrate and an optical waveguide. The substrate has a rectangular area sandwiched by first and second end faces opposing each other. The optical waveguide is formed in the rectangular area and has a single input waveguide exposed on the first end face of the rectangular area, and a plurality of branched waveguides exposed on the second end face of the rectangular area. The optical waveguide is branched into 2.sup.n by repeating branching into two waveguides from the first to second end face of the rectangular area. The input waveguide is optically connected to a single-type optical fiber, and the branched optical waveguides are optically connected to a multi-type array optical fiber.

Single-type array optical conversion apparatus

A light receiving element is comprised of a light sensitive surface on a semiconductor substrate and a positive electrode (anode), a negative electrode (cathode), a mounting precision test mask, a conductive electrode wire, and solder resist on the same substrate surface. A metal thin film, a mounting alignment mark, and a mounting precision mark window are provided on the back side of the substrate. Two or more electrode surfaces having either the anode or the cathode used as the common electrode are provided. The light sensitive surface is positioned approximately in the center between these two electrode surfaces. A highly precise mounting can therefore be achieved with the solder bump, even when mounting single light receiving elements. High precision mounting is also obtained when mounting light receiving element arrays. This type of light receiving element can be precisely positioned and bonded by solder bumps to a substrate having an optical fiber fitted in the V groove.

Light receiving device for use in optical fiber communications and the

The optical fibers are arranged in a V groove formed at the surface of a silicon substrate and a cover is provided thereon. An electrode for solder bump is respectively formed at the position opposed with each other to the substrate and cover. These substrate and cover are deposited with solder in order to fix the optical fibers. The substrate or cover is previously provided, at the end point part of the optical fibers, with the mark for the positioning in the longitudinal direction of the optical fibers. The optical fibers are positioned with this mark. Here, the side surface of the optical fibers is provided with the metallized area at the position located in the predetermined distance from the end point thereof. Before fixing with the cover, the optical fibers can be deposited automatically to the predetermined position without alignment due to the self-alignment effect between the mark and metallized area. Meanwhile, the optical element can be deposited with the solder bump without adjustment to the area near the end point of the optical fiber by utilizing the self-alignment. Here, it is also possible to form the mark to the substrate for measuring the mounting position of the optical element after deposition thereof.

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Tokyo, Japan

Isao Yoneda