High etching rates of HVPE GaN, up to 2 mu m/min, have been achieved by photoelectrochemical etching to produce stripes which are 70-100 mu m high. These wafers have been used as substrates for subsequent HVPE growth. The surface after the second growth was irregular and needed to be polished prior to defect density evaluation. The dislocation densities measured by the defect-selective etching were 2 X 10(7) cm(-2) and 3 X 10(5) cm(-2) in the stripe region and the low-dislocation-density lateral growth region, respectively. The low-dislocation-density regions formed stripes of about 10 mu m. (c) 2008 Elsevier B.V. All rights reserved.