Two-dimensional electron gas (2DEG) at perovskite oxide heterostructure has generated intense attentions owing to their peculiar physical properties of Al2O3/SrTiO3 hetero structures.[1]
Interestingly, high density electrons up to (1013~1014/cm2) were confined at the interface of Al2O3 layer grown on single crystalline STO substrate by atomic layer deposition (ALD). Its electron density is 100 times higher than that of the conventional semiconductor heterojunction, which enables high on current in the transistor.
Recently, potential applications of the oxide heterostructures for gas/photo sensors have attracted great research interests. In this work, we demonstrate a highly sensitive hydrogen gas sensor using Pd-decorated Al2O3/SrTiO3 heterostructures.
Surprisingly, Al2O3/SrTiO3 heterostructure with the Pd exhibited significantly high sensitivity to hydrogen gas owing to its 2-dimensional properties.
