Cathodoluminescence Spectroscopy in Graded InxGa1-xN

Xiaofang Zhao; Tao Wang; Bowen Sheng; Xiantong Zheng; Li Chen; Haihui Liu; Chao He; Jun Xu; Rui Zhu; Xinqiang Wang

doi:10.3390/nano12213719

Cathodoluminescence Spectroscopy in Graded In_xGa_1-xN

Nanomaterials (Basel). 2022 Oct 23;12(21):3719. doi: 10.3390/nano12213719.

Authors

Xiaofang Zhao¹, Tao Wang², Bowen Sheng³, Xiantong Zheng³, Li Chen², Haihui Liu¹, Chao He⁴, Jun Xu², Rui Zhu², Xinqiang Wang³

Affiliations

¹ School of Materials Science and Engineering, Tiangong University, Tianjin 300387, China.
² Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China.
³ State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing 100871, China.
⁴ Beijing Goldenscope Technology Co., Ltd., Beijing 100190, China.

Abstract

InGaN materials are widely used in optoelectronic devices due to their excellent optical properties. Since the emission wavelength of the full-composition-graded In_xGa_1-xN films perfectly matches the solar spectrum, providing a full-spectrum response, this makes them suitable for the manufacturing of high-efficiency optoelectronic devices. It is extremely important to study the optical properties of materials, but there are very few studies of the luminescence of full-composition-graded In_xGa_1-xN ternary alloy. In this work, the optical properties of full-composition-graded In_xGa_1-xN films are studied by cathodoluminescence (CL). The CL spectra with multiple luminescence peaks in the range of 365-1000 nm were acquired in the cross-sectional and plan-view directions. The CL spectroscopy studies were carried out inside and outside of microplates formed under the indium droplets on the InGaN surface, which found that the intensity of the light emission peaks inside and outside of microplates differed significantly. Additionally, the paired defects structure is studied by using the spectroscopic method. A detailed CL spectroscopy study paves the way for the growth and device optimization of high-quality, full-composition-graded In_xGa_1-xN ternary alloy materials.

Keywords: cathodoluminescence; full-composition-graded InxGa1−xN films; nitride semiconductor; paired defects.

Grants and funding

This research was funded by the National Natural Science Foundation of China, grant number 61904002; and the Key-Area Research and Development Program of Guangdong Province, grant number 2018B030327001.