Over 6 μm thick MOCVD-grown low-background carrier density (1015 cm-3) high-mobility (010) β-Ga2O3 drift layers

This work reports high carrier mobilities and growth rates simultaneously in low unintentionally doped (UID) (10(15) cm(-3)) metalorganic chemical vapor deposition (MOCVD)-grown thick beta-Ga2O3 epitaxial drift layers, with thicknesses reaching up to 6.3 mu m, using triethylgallium (TEGa) as a precursor. Record-high room temperature Hall mobilities of 187-190 cm(2)/V s were measured for background carrier density values of 2.4-3.5 x 10(15) cm(-3) grown at a rate of 2.2 mu m/h. A controlled background carrier density scaling from 3.3 x 10(16) to 2.4 x 10(15) cm(-3) is demonstrated, without the use of intentional dopant gases such as silane, by controlling the growth rate and O-2/TEGa ratio. Films show smooth surface morphologies of 0.8-3.8 nm RMS roughness for film thicknesses of 1.24-6.3 mu m. Vertical Ni Schottky barrier diodes (SBDs) fabricated on UID MOCVD material were compared with those fabricated on hydride vapor phase epitaxy material, revealing superior material and device characteristics. MOCVD SBDs on a 6.3 mu m thick epitaxial layer show a uniform charge vs depth profile of similar to 2.4 x 10(15) cm(-3), an estimated mu(drift) of 132 cm(2)/V s, breakdown voltage (V-BR) close to 1.2 kV, and a surface parallel plane field of 2.05 MV/cm without any electric field management-setting record-high parameters for any MOCVD-grown beta-Ga2O3 vertical diode to date.