High-Quality and Strain-Relaxation GaN Epilayer Grown on SiC Substrates Using AIN Buffer and AlGaN I

• 作 者: 刘波亭 郭仕宽 马平 王军喜 李晋闽
• 机 构: Semiconductor Lighting R&D Center, Institute of Semiconductors, Chinese Academy of Sciences,College
• 出 处: Chinese Physics Letters
• 发表日期: 2017年04期
• 关键词: AlGaN interlayer relaxation tensile crystalline Strain yellow ultraviolet Buffer

We study the effect of the AlGaN interlayer on structural quality and strain engineering of the GaN films grown on SiC substrates with an AIN buffer layer. Improved structural quality and tensile stress releasing are realized in unintentionally doped GaN thin films grown on 6 H—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 crystalline 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.

We study the effect of the AlGaN interlayer on structural quality and strain engineering of the GaN films grown on SiC substrates with an AIN buffer layer. Improved structural quality and tensile stress releasing are realized in unintentionally doped GaN thin films grown on 6 H-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 crystalline 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 . By by the alGaN interlayer, we could acquire the high-quality and strain-relaxation GaN epilayer with large thickness on SiC subst rates.