Large area GaN and AlN template substrates fabricated by HVPE

Abstract

AbstractHydride vapour phase epitaxy (HVPE) is known as fast deposition method to produce both free‐standing GaN substrate materials and thick low‐defect GaN on 2‐inch sapphire and AlN layers on 2‐inch sapphire and conductive silicon carbide (SiC) substrates. These substrate materials of 2‐inch size are available as commercial product. In this paper, we extend the HVPE abilities to new fields including up to 23 μm thick crack‐free AlN layers growth on 3‐inch and 100‐mm SiC substrates (AlN/SiC template substrates) and up to 125 μm thick GaN layers grown on 3‐inch sapphire (GaN/sapphire template substrates). For 21‐23 μm thick AlN layers grown on 100‐mm SiC substrates, the X‐ray rocking curve FWHM was ranged from 200 to 300 arc sec and from 600 to 800 arc sec for the (00.2) and the (10.2) AlN reflections, respectively. For 115‐125 μm thick GaN layers, the X‐ray FWHM values were 120‐150 arcsec and 200‐230arc sec for the (00.2) and the (10.2) GaN reflections, respectively, that corresponds screw dislocation density of (3‐5)×107 cm–2 evaluated based on XRD data. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)