Confinement of Electrons at the LaInO<sub>3</sub>/BaSnO<sub>3</sub> Heterointerface
Daniel Pfützenreuter, Seonghyeon Kim, Hyeongmin Cho, Oliver Bierwagen, Martina Župančić, M. Albrecht, K. Char, Jutta Schwarzkopf
Abstract
Abstract The properties of the conductance at the LaInO 3 /BaSnO 3 heterointerface are reported. The heterointerface is formed by covering the semi‐insulating BaSnO 3 :La thin films with 10 nm LaInO 3 films, which are all epitaxially grown on NdScO 3 substrates. Structural properties of BaSnO 3 thin films are investigated by means of X‐ray diffraction and transmission electron microscopy and exhibit a threading dislocation density of 6 × 10 10 cm −2 . Via capacitance–voltage ( C–V ) measurements, clear evidence is present for the accumulation of electrons at the interface within 2.5 nm in the BaSnO 3 layer, confirming the formation of a 2D electron gas (2DEG). Additionally, temperature dependent Hall effect measurements reveal a semiconducting behavior of the electron density of the 2DEGs. The room temperature mobility of 22 cm 2 V −1 s −1 at an electron density of 4 × 10 13 cm −2 is found to increase as the temperature decreases to 25 K.