Sanken Electric Co., Ltd.

Nobuhisa Sugimori

Koji Otsuka

Hitoshi Murofushi

Hideyuki Watanabe

A light emitting device includes: a first semiconductor region; a second semiconductor region and third semiconductor region which are provided in the first semiconductor region; a first semiconductor light emitting element of which first electrode is electrically connected to a main surface of the second semiconductor region; a second semiconductor light emitting element of which third electrode is electrically connected to a main surface of the third semiconductor region; and a conductor which electrically connects the second electrode of the first semiconductor light emitting element and the third semiconductor region, and which electrically connects the second electrode and the third electrode through the third semiconductor region. In the light emitting device, the semiconductor light emitting elements are connected in series, and are directly connected to a power source.

Light emitting device

An LED comprises a multilayered light-generating semiconductor region grown on one of a pair of opposite major surfaces of a semiconducting silicon substrate, a bonding pad overlying the light-generating semiconductor region and received in part in a cavity formed centrally therein, and a substrate electrode on the other major surface of the substrate. For protecting the LED from voltage spikes or like transients, an overvoltage protector such as a Schottky barrier diode is interposed between the bonding pad and the substrate. Further, for a uniform current distribution throughout the light-generating semiconductor region, a current-spreading film of electrically conducting, optically transparent material overlies the light-generating semiconductor region and itself covered by a transparent overlay of electrically insulating material. The bonding pad is electrically coupled to the current-spreading film via a plurality of connector strips extending radially from the pad over the transparent overlay. The connector strips have ribs depending therefrom and extending through radial slits in the transparent overlay into electrical contact with the current-spreading film.

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Niiza, Japan

Nobuhisa Sugimori