Fabrication of GaN/AlN bilayer particles by a vapor phase method

Abstract

AbstractIn contrast to the conventinal powder phosphors consisting of particles with a uniform material composition, GaN‐based nanostructure‐embedded particles, which consist of GaN quantum dots or quantum wells in the AlN matrix, has been proposed. We can expect the novel phosphors to have higher luminescence efficiencies owing to the carrier confinement effect. As a fundamental technique to fabricate such particles, the formation of bilayer particles consisting of an AlN core and a GaN surface layer has been demonstrated by using the two‐stage vapor phase method. The AlN particles were first formed by a reaction of vaporized Al and N2 gas at temperatures from 1100 to 1250 °C in the first reactor, followed by the growth of GaN on the core surface by a reaction of GaCl and NH3 at 1000 °C in the second reactor. Thus fabricated GaN/AlN bilayer particles showed cathodoluminescence dominated by the band edge emission of GaN. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)