Investigation of β‐Ga2O3 Film Growth Mechanism on c‐Plane Sapphire Substrate by Ozone Molecular Beam Epitaxy. Issue 4 (6th December 2020)

• Record Type: Journal Article
• Authors: Feng, Boyuan; Li, Zhengcheng; Cheng, Feiyu; Xu, Leilei; Liu, Tong; Huang, Zengli; Li, Fangsen; Feng, Jiagui; Chen, Xiao; Wu, Ying; He, Gaohang; Ding, Sunan
• Is Part Of: Physica status solidi. Volume 218:Issue 4(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-12-06
• Subjects: molecular beam epitaxial -- oxides -- surface morphology -- X-ray diffraction; Solid state physics -- Periodicals; Solids -- Industrial applications -- Periodicals; 530.41
• DOI: 10.1002/pssa.202000457
• Languages: English
• ISSNs: 1862-6300

Abstract

Abstract : Growth mechanism and temperature of monoclinic gallium oxide (β‐Ga2 O3 ) films grown by ozone molecular beam epitaxy (MBE) are investigated herein. Phase‐pure ( 2 ¯ 01 ) β‐Ga2 O3 films can be grown on c ‐plane sapphire substrates when the growth temperature exceeds 500 °C, and the grain size increases with the increase in the growth temperature. Sixfold rotational domains are obtained based on the epitaxial relationships (Ga2 O3 < 010>//Al2 O3 < 1 1 ¯ 00 > and Ga2 O3 < 102>//Al2 O3 < 11 2 ¯ 0>). For the film grown at 700 °C, the threefold facets are observed for the first time, which are resulted from the easy‐cleaved (100) plane and rotational domains. In addition, the cathodoluminescence spectra of the β‐Ga2 O3 films show that the proportion of ultraviolet emission increases with the increase in the growth temperature, which is attributed to the modulation of defect. Finally, the growth rate can be modulated by the ratio of Ga flux and ozone pressure. A reference is provided for heteroepitaxy of β‐Ga2 O3 films and better understanding of the ozone MBE growth mechanism of oxides. Abstract : β‐gallium oxide (β‐Ga2 O3 ) films are grown on c ‐plane sapphire substrates using molecular beam epitaxial technique with pure ozone as the oxygen source. For the film grown at 700 °C, threefold facets are first observed as the distinct feature of surface morphology, which can be formed due to the easy‐cleaved (100) plane and rotational domains.