| Title |
Growth and Controlled Si Doping in Homoepitaxial β-Ga2O3 Films by Plasma-Assisted Molecular Beam Epitaxy |
| Authors |
(Nguyen Quoc Vuong) ; (Nguyen Quoc Vuong) ; (Trong Si Ngo) ; (Raouf Hayyak) ; 박지현(Taswar Iqbal) ; 전대우(Ji-Hyeon Park) ; 홍순구(Dae-Woo Jeon) |
| DOI |
https://doi.org/10.3365/KJMM.2025.63.9.711 |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
Gallium oxide; Doping; Homoepitaxy; Molecular beam epitaxy |
| Abstract |
The growth evolution of undoped and Si-doped ?-Ga2O3 films prepared using plasma-assisted
molecular beam epitaxy was investigated. The effect of Si effusion cell temperatures on surface morphology
and the electrical properties of the homoepitaxial (010) ?-Ga2O3 films was systematically investigated. Using
a solid source of Si as an n-type dopant in ?-Ga2O3 films has been challenging because the growth environment
is normally oxygen-rich and Si is easily oxidized, which results in uncontrollable doping. The issue of solid
Si source oxidation in the oxidizing growth environment could be solved by decreasing the exposed surfaces
of the Si solid source inside the crucible of the Si effusion cell. We fully melted pieces of the chip-shaped solid
Si source with large surface areas and solidified them again. This effectively reduced the Si source surface
so that only the top surface of the solidified Si in the crucible was exposed. By employing this simple method,
we could control carrier concentrations of Si-doped ?-Ga2O3 films from 8.25×1018 cm-3 to 2.18×1020 cm-3. The
surface morphology of the (010) Si-doped ?-Ga2O3 films showed the features of [001] crystal orientationelongated
stripes and grooves. The homoepitaxial (010) Si-doped ?-Ga2O3 films showed smooth surfaces with
root mean square roughness values of less than 1.4 nm. |