High power devices based on gallium nitride and aluminum gallium nitride semiconductor heterostructures

Abstract

High power thyristor-type devices comprising a first layer of p-type doped semiconductor alloy aluminum gallium nitride, a second layer of n-type doped aluminum gallium nitride with lower aluminum content than the first layer, a third layer of p-type doped aluminum gallium nitride with a higher aluminum content than the second layer, and a fourth layer of aluminum gallium nitride of n-type doping. The difference in hole and electron energies (band offsets) across the interface between aluminum gallium nitride and gallium nitride are such that hole and electron transfer are enhanced from aluminum gallium nitride to gallium nitride, or hole and electron transfer are suppressed from gallium nitride to aluminum gallium nitride. Aluminum content in layers 1 and 2 is chosen such that hole transfer in the forward biased conduction state of the device is enhanced, and suppressed in the reverse biased blocking state of the device. Aluminum content in layers 2 and 3 is chosen such that hole transfer in the forward biased blocking state of the device is suppressed, which reduces leakage current and enhances hole transfer into layer 2 when the device is changing from the forward biased blocking state to the forward biased conduction state. Triggering of the device may be provided by a gate contact to the third layer. Various exemplary embodiments are disclosed.

Dependencies are inferred from the claim text.