Hydride vapor phase epitaxy of AlN: thermodynamic analysis of aluminum source and its application to growth

Abstract

A thermodynamic analysis of the generation of gaseous aluminum chlorides by the reaction between aluminum (Al) metal and hydrogen chloride (HCl) gas is described for hydride vapor phase epitaxy (HVPE) of AlN. Regardless of the hydrogen mole fraction in the carrier gas, the major species of aluminum chloride is AlCl when the temperature of the Al metal is above 790 °C and is AlCl3 when the temperature is below 790 °C. Since AlCl3 is less reactive with quartz (SiO2) than AlCl, HVPE of AlN is possible using AlCl3 and NH3 even with a conventional system having a quartz reactor. Successful AlN HVPE on sapphire substrates is also reported. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)