Characterization and Mitigation of Resistive Losses in a Large Area Laser Power Converter.

摘要

GaAs Laser Power Converters (LPC) were simulated in 2D and 3D under 10 W/cm2 illumination of 810 nm light using Synopsys Sentaurus software revealing significant dependence of effciency on grid metal finger spacings, S, and finger dimensions. Efficiency results were comparable to an experimental efficiency of 53.4% cited in the literature for an LPC under 43 W/cm2 of 810 nm laser light. 2D devices were simulated with S of 20 - 1000 micrometer revealing an efficiency drop, Delta(n), with increasing spacings. The efficiency drop was reduced from Delta(n) of 39.43% at S = 740 micrometer to Delta(n) of 14.38% at S = 1000 micrometer when modifying the window layer to include a highly doped lateral conduction layer (LCL). In the 3D simulations, resistive losses in the grid metal fingers were reduced by thickening the grid metal from 3 micrometer x 0.5 micrometer with an efficiency of 26% at an effective length of 0.5 cm up to 10 micrometer x 5 micrometer, achieving an efficiency of 44.89% at an effective finger length of 1 cm. An LCL and thicker fingers are shown to be critical for designing large area LPCs to convert laser light to electrical power for devices such as small RPAs and tactical sensors.