Migration Enhanced Metalorganic Chemical Vapor Despsition of AlN/GaN/InN based heterostructures
Qhalid Fareed1, TRemis Gaska1, Juras Mickenvicius2, Gintautas Tamulaitis2, Michael S. Shu2, M. Asif Khan3
1Sensor Electronic Technology Inc.,
2Rensselaer Polytechnic Institute,
3Department of Electrical Engineering,
Keywords: MEMOCVD, Nitrides, large area substrates, HEMT
We applied a new Migration Enhanced Metalorganic Chemical Vapor Deposition (MEMOCVDTM) epitaxial technique for growing AlN/GaN/InN epitaxial films and heterostructure layers on 2”. 3” and 4” substrates. The growth of the AlN/GaN/InN layers was carried out using controlled precursor pulsed flows to achieve accurate thickness control over large area substrates. This technique bridges the gap between molecular beam epitaxy (MBE) and metalorganic chemical vapor deposition (MOCVD). The Al composition in AlGaN barrier layer of AlGaN/GaN high electron mobility transistor (HEMT) structures varied less than 3% over 3” and 4” wafers. For AlGaN/GaN HEMTs, the sheet resistance of 463 ohm/sq has been achieved over a 4” diameter wafer grown on sapphire. The MEMOCVD technique ensures an improved material quality resulting in a better device performance. The technology should also find applications for nitride photonic devices, such as deep ultraviolet light emitting diodes, ultraviolet lasers, and solar blind ultra violet photodetectors.