β-Ga2O3 nanowires: controlled growth, characterization, and deep-ultraviolet photodetection application

Abstract

Abstract We investigate the growth of ( 2 ˉ 01 ) β-Ga2O3 nanowires with a GaN seed crystal in detail. Growth of ( 2 ˉ 01 ) β-Ga2O3 nanowires starts with the formation of (001) Ga(II)–O chains of octahedral Ga2O6 structures, indicating the initial formation of ( 2 ˉ 01 ) and (001) atomic facets of β-Ga2O3 nanowires. Subsequent growth of Ga2O3 leads to the formation of (100) Ga(I)–O chains and energetically stable (100) and (010) sidewalls and octahedral Ga2O6 structures in the β-Ga2O3 nanowires. Energetically stable tetrahedral GaO4 structures are eventually formed in the β-Ga2O3 nanowires. High-quality N-doped ( 2 ˉ 01 ) β-Ga2O3 nanowires are synthesized and growth kinetics is clarified. The β-Ga2O3 nanowires deep-ultraviolet photodetectors show superior performance with high photoresponsivity (3.5 × 103 A W−1) and detectivity (9.6 × 1015 Jones) at −10 V bias.