Structural and Electrical Characterization of Solution‐Deposited β‐Ga₂O₃:Al

Abstract

The wide bandgap oxide semiconductor thin films are synthesized using tetrahydroxogallate (III) ammonium {NH4Ga(OH)4} precursor at a concentration of 10 at% Ga and varying amounts of hydrated aluminum nitrate between 0.6 and 3.2 at%. Thin films of β‐Ga2O3:Al are synthesized by spin coating and spray pyrolysis with postannealing in nitrogen ambient at 930 °C. The structural properties of the thin films are investigated using XRD and Raman spectroscopy, while the electrical characteristics are determined using 4‐point probe, current–voltage (I–V), and capacitance–voltage (C–V) measurements with Ti/Al/Ni/Au Ohmic contacts and Pd/Au Schottky contacts. The β‐Ga2O3 with 2.2 at% Al is found to be the optimal concentration in this study, resulting in ideality factors of 1.10 and 1.09, saturation currents of 3.17 × 10−6 and 3.10 × 10−6 A, Schottky barrier heights of 0.73 and 0.88 eV, and series resistances of 948 and 955 Ω, for the spin‐coated and pyrolytically sprayed samples respectively.