P-contact for GaN-based semiconductors utilizing a reverse-biased tunnel junction

摘要

A light-generating device such as a laser or LED. A light-generating device according to the present invention includes a first n-electrode layer in contact with a first n-contact layer, the first n-contact layer including an n-doped semiconductor. Light is generated by the recombination of holes and electrons in an n-p active layer. The n-p active layer includes a first p-doped layer in contact with a first n-doped layer, the first n-doped layer being connected electrically with the first n-contact layer. A p-n reverse-biased tunnel diode constructed from a second p-doped layer in contact with a second n-doped layer is connected electrically such that the second p-doped layer is connected electrically with the first p-layer. A second n-contact layer constructed from an n-doped semiconductor material is connected electrically to the second n-doped layer. A second n-electrode layer is placed in contact with the second n-contact layer. The various layers of the invention can be constructed from GaN semiconductors. The p-n reverse-biased tunnel diode includes an n-depletion region in the second n-doped layer and a p-depletion region in the second p-doped layer, the n-depletion region and the p-depletion region in contact with one another. The conductivity of the reverse-bias tunnel diode may be increased by doping the n-depletion region and p-depletion region. The conductivity of the reverse-bias tunnel diode can also be increased by including a compressively strained InGaN layer in the n-depletion region.