Abstract
Surface electronic states and band bending behavior of the corundum In2O3 (α-In2O3), which is a metastable crystal polymorph, thin film grown by mist-chemical vapor deposition was investigated by combining hard and soft X-ray photoelectron spectroscopy (HAXPES and SXPES, respectively) by comparison with the bixbyite In2O3 (cubic-In2O3) thin films. Regardless of the crystal structure, the surfaces have surface electron accumulation layers (SEALs). Although the α-In2O3 film indicated the wider bandgap than the cubic-In2O3 film, the Fermi level of the α-In2O3 film pined above the conduction band minimum by approximately 0.6 eV, which was the same value as the cubic-In2O3 film. The bulk and surface carrier densities for the α-In2O3 film were estimated as 3.9 × 1017 and 6.0 × 1019 cm−3 by combining the HAXPES results and the Poisson–Schrödinger solutions, respectively. The SEAL is formed regardless of the crystallographic symmetry of In2O3, which should relate with the surface bonding state of In.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
