Background: GaN grown on Si substrate have high leakage current and limited breakdown voltage due to conducting Si substrate. Technology Description: This invention introduces three new GaN-on-Si substrate structures that increase nitride transistor breakdown voltage reduce device leakage improve nitride material quality and potentially produce free standing GaN wafers. The new substrates use three different structures to block the leakage current through the substrate and substrate/nitride interface: (a) p-n junctions on the top Si surface (b) p-n junctions above an oxide layer (c) Si pillars above oxide. Applications: High voltage power electronics power amplification hybrid vehicles high efficient power inverters for solar cells power converters for LEDs
Reduces leakage current so that GaN transistors with breakdown voltages above 300V can be achieved.