High Flux Atomic Nitrogen Source for GaN Growth

Current gallium nitride epitaxial growth systems suffer from low atomic nitrogen flux density, yielding materials having high intrinsic conduction due to nitrogen deficiencies or defects. A number of atomic nitrogen sources exist for MBE epitaxial growthof gallium nitride but the flux density is relatively low and these sources still contain a significant percentage of molecular nitrogen in the beam which can lead to defects. Nanohmics proposes to use a high-flux-density atomic nitrogen source for defectfree epitaxial gallium nitride (GaN) growth. This unique nitrogen source uses using supersonic beam technology. This technology will greatly increase the atomic nitrogen flux density striking the surface during growth.Supersonic beams have a number of advantages over conventional gas sources. First, the mean free path is longer than the source-to-sample distance eliminating gas-gas interactions therefore the atomic nitrogen will not recombine. Secondly, supersonicbeams are monoenergetic and the kinetic energy of the incident beam can be varied by changing the input gas temperature. Therefore this source can deliver a very high flux density of monoenergetic atomic nitrogen to the sample which can influence thesurface mobility and the defect density. The anticipated benefits of a high-flux-density atomic nitrogen source are improved gallium nitride growth with lower intrinsic carrier densities. The improved gallium nitride will lead to improvements in detectors for space communications, space-basedmissile launch detectors, UV search and track, environmental monitoring, engine combustion, UV diode lasers, and flame detection. Additional benefits will be in high power electronics using GaN based devices.