High-efficiency, overvoltage-protected, light-emitting semiconductor device

Abstract

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.