Native defects association enabled room-temperature p-type conductivity in β-Ga2O3

The room temperature hole conductivity of the ultra-wide bandgap semiconductor beta-Ga2O3 is a pre-requisite for developing the next-generation electronic and optoelectronic devices based on this oxide. In this work, high-quality p-type beta-Ga2O3 thin films grown on r-plane sapphire substrate by metalorganic chemical vapor deposition (MOCVD) exhibit rho = 5x10(4) ohmcm resistivity at room temperature. A low activation energy of conductivity as E-a2 = 170 +/- 2 meV was determined, associated to the V-O(++) - V-Ga(-) native acceptor defect complex. Further, taking advantage of cation (Zn) doping, the conductivity of Ga2O3:Zn film was remarkably increased by three orders of magnitude, showing a long-time stable room-temperature hole conductivity with the conductivity activation energy of around 86 meV. V-O(++)-Zn-Ga(-) defect complex has been proposed as a corresponding shallow acceptor.

Automated summary

The room temperature hole conductivity of β-Ga2O3 was achieved by growing high-quality films on a sapphire substrate. The conductivity was significantly enhanced by zinc doping with low activation energy.