High-Quality and Strain-Relaxation GaN Epilayer Grown on SiC Substrates Using AlN Buffer and AlGaN Interlayer

• 来源期刊: 中国物理快报（英文版）
• 关键词: @@
• 年，卷（期）: 2017,（4）
• 页码范围: 108-111
• 页数: 4页
• 语种: 英文
• DOI: 10.1088/0256-307X/34/4/048101

摘要

We study the effect of the A1GaN interlayer on structural quality and strain engineering of the GaN films grown on SiC substrates with an A1N buffer layer.Improved structural quality and tensile stress releasing are realized in unintentionally doped GaN thin films grown on 6H-SiC substrates by metal organic chemical vapor deposition.Using the optimized AlGaN interlayer,we find that the full width at half maximum of x-ray diffraction peaks for GaN decreases dramatically,indicating an improved crystalfine quality.Meanwhile,it is revealed that the biaxial tensile stress in the GaN film is significantly reduced from the Raman results.Photoluminescence spectra exhibit a shift of the peak position of the near-band-edge emission,as well as the integrated intensity ratio variation of the near-band-edge emission to the yellow luminescence band.Thus by optimizing the AlGaN interlayer,we could acquire the high-quality and strain-relaxation GaN epilayer with large thickness on SiC substrates.