p‐Type β‐Ga₂O₃ Homoepitaxial Films with Superior Electrical Transport Properties

This work reports high structural quality and exceptional electrical transport properties of homoepitaxial β ‐Ga 2 O 3 thin films grown by Metal–Organic Chemical Vapor Deposition (MOCVD) on (010)‐ and (–201)‐oriented substrates. (010) β ‐Ga 2 O 3 samples exhibit mobility of up to 69.4 cm 2 (V·s) −1 and stable hole concentrations ≈2.4 × 10 17 cm −3 from 370 to 700 K. Structural and morphological studies, including XRD, AFM, and STEM, confirm high epitaxial quality, absence of extended defects and minimal strain. (–201) β‐ Ga 2 O 3 layer, which is simultaneously grown, exhibits typical p ‐Ga 2 O 3 behavior with observed deep level defects. The hole mobility ranging from 26 to 36 cm 2 V −1 ·s −1 is measured between 420 and 700 K. Comparison of (010) and (–201) orientations reveals distinct anisotropic electrical properties. The findings emphasize the free motion of holes in β‐ Ga 2 O 3 and the critical role of crystallographic orientation.