US Patent 9224805 Semiconductor devices with guard rings

Semiconductor devices with guard rings are described. The semiconductor devices may be, e.g., transistors and diodes designed for high-voltage applications. A guard ring is a floating electrode formed of electrically conducting material above a semiconductor material layer. A portion of an insulating layer is between at least a portion of the guard ring and the semiconductor material layer. A guard ring may be located, for example, on a transistor between a gate and a drain electrode. A semiconductor device may have one or more guard rings.