Structure and luminescence of α-plane GaN on γ-plane sapphire substrate modified by Si implantation

• 作者: Lijie Huang Lin Li Zhen Shang Mao Wang Junjie Kang Wei Luo Zhiwen Liang Slawomir Prucnal Ulrich Kentsch Yanda Ji Fabi Zhang Qi Wang Ye Yuan Qian Sun Shengqiang Zhou Xinqiang Wang
• 来源期刊: 中国物理B（英文版）
• 年，卷（期）: 2021,（5）
• 所属期刊栏目: SPECIAL TOPIC—Ion beam modification of materials and applications
• 页码范围: 69-75
• 页数: 7页
• 语种: 英文
• DOI: 10.1088/1674-1056/abd76a

摘要

We show the structural and optical properties of non-polar a-plane GaN epitaxial films modified by Si ion implan-tation.Upon gradually raising Si fluences from 5×1013 cm-2 to 5×1015 cm-2,the n-type dopant concentration grad-ually increases from 4.6×1018 cm-2 to 4.5×1020 cm-2,while the generated vacancy density accordingly raises from 3.7×1013 cm-2 to 3.8×1015 cm-2.Moreover,despite that the implantation enhances structural disorder,the epitax-ial structure of the implanted region is still well preserved which is confirmed by Rutherford backscattering channeling spectrometry measurements.The monotonical uniaxial lattice expansion along the a direction(out-of-plane direction)is observed as a function of fluences till 1×1015 cm-2,which ceases at the overdose of 5×1015 cm-2 due to the partial amorphization in the surface region.Upon raising irradiation dose,a yellow emission in the as-grown sample is gradually quenched,probably due to the irradiation-induced generation of non-radiative recombination centers.