Halide Vapor Phase Epitaxy α‐ and ε‐Ga₂O₃ Epitaxial Films Grown on Patterned Sapphire Substrates

Abstract

The growth of Ga2O3 films by halide vapor phase epitaxy on plain and cone‐shaped patterned sapphire substrates (PSS) is reported. The obtained specimens are characterized by X‐ray diffraction, transmission electron microscopy, cathodoluminescence, optical transmission spectroscopy, and current–voltage measurements. Both types of Ga2O3 layers are of reasonably high crystal qualities; their physical properties, however, are very different. Under the same conditions, the growth on plain substrates results in a continuous α‐Ga2O3 layer, whereas the growth on PSS produces a regular array of α‐Ga2O3 columns on top of the sapphire cones with the space between them filled with ε‐Ga2O3. Ga2O3 films grown on plain sapphire are insulating; in contrast, Ga2O3 films grown on PSS are conducting. It is found that the conductivity of Ga2O3 on PSS follows the Arrhenius law with the activation energy of 0.33 eV. New luminescent bands for α‐ and ε‐phases are found. Spectral components of the defect‐related luminescence for α‐ and ε‐ phases are identified.

Reduction of dislocations in α-Ga2O3 epilayers grown by halide vapor-phase epitaxy on a conical frustum-patterned sapphire substrate

“…We assumed that the -phase was grown at the top and bottom of the CF-PSS, and the "-phase was grown on the sidewall of the CF-PSS. In a previous report, Shapenkov et al (2020) confirmed that an -Ga 2 O 3 epilayer was grown on the top of the pattern, and an "-Ga 2 O 3 epilayer was grown on the sidewall of the pattern. The 004 diffraction peak position of the -Ga 2 O 3 epilayer was observed at 38.85 (JCPDS No.…”

60 Years of physica status solidi

“…The articles raising the most attention in the form of citations within the year of appearance 2020 are listed below. [ 1–6 ]…”

Влияние влажности окружающей среды на электрическую проводимость полиморфных Ga-=SUB=-2-=/SUB=-O-=SUB=-3-=/SUB=--структур

“…Достигнут значительный прогресс в выращивании эпитаксиальных пленок [1][2][3][4][5][6][7][8][9]. Корундообразная α-фаза обладает среди всех политипов оксида галлия наибольшей шириной запрещенной зоны E g , не менее 5.3 эВ, и при легировании Sn или Si имеет высокую донорную проводимость [3,8,[10][11][12][13][14][15]. В то же время ε-фаза с E g , близкой к 4.9 эВ [1,2,16], является второй после β-Ga 2 O 3 по температурной стабильности.…”