Comparison study of GaN films grown on porous and planar GaN templates**Project supported by the National Key R&D Program of China (Grant No. 2017YFB0404201), the State Key R&D Program of Jiangsu Province, China (Grant No. BE2019103), the Six-Talent Peaks Project of Jiangsu Province, China (Grant No. XCL-107), the Fund from the Solid-state Lighting and Energy-saving Electronics Collaborative Innovation Center, PAPD,

Abstract

The GaN thick films have been grown on porous GaN template and planar metal-organic chemical vapor deposition (MOCVD)-GaN template by halide vapor phase epitaxy (HVPE). The analysis results indicated that the GaN films grown on porous and planar GaN templates under the same growth conditions have similar structural, optical, and electrical properties. But the porous GaN templates could significantly reduce the stress in the HVPE-GaN epilayer and enhance the photoluminescence (PL) intensity. The voids in the porous template were critical for the strain relaxation in the GaN films and the increase of the PL intensity. Thus, the porous GaN converted from β-Ga2O3 film as a novel promising template is suitable for the growth of stress-free GaN films.