Determination of dislocation density in epitaxially grown GaN using an HCl etching process

Dislocation analysis of epitaxially grown GaN was performed using an HCl vapor phase etching process. The effects of the major process parameters temperature, pressure and gas composition have been studied in detail. For reliable results a large size of the etch pits is required, but a merging of the pits has to be avoided. A temperature of 600 degreesC, a reactor pressure of 940 mbar and an HCl concentration of 10% lead to best results and highest etch rates, respectively (C) 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Wemheim