This paper reports a new p-type tin oxyselenide (SnSeO), which was designed with the concept that the valence band edge from O 2p orbitals in the majority of metal oxides becomes delocalized by hybridizing Se 4p and Sn 5s orbitals. As the Se loading increased, the SnSeO film structures were transformed from tetragonal SnO to orthorhombic SnSe, which was accompanied by an increase in the amorphous phase portion and smooth morphologies. The SnSe0.56O0.44 film annealed at 300 °C exhibited the highest Hall mobility (μHall), 15.0 cm2 (V s)-1, and hole carrier density (nh), 1.2 × 1017 cm-3. The remarkable electrical performance was explained by the low hole effective mass, which was calculated by a first principle calculation. Indeed, the fabricated field-effect transistor (FET) with a p-channel SnSe0.56O0.44 film showed the high field-effect mobility of 5.9 cm2 (V s)-1 and an ION/OFF ratio of 3 × 102. This work demonstrates that anion alloy-based hybridization provides a facile route to the realization of a high-performance p-channel FET and complementary devices.
Keywords: Sn−Se−O; high mobility; p-type inorganic semiconductor; thermal stability; valence band engineering.