We report the characteristics of thin-film transistor (TFT) to make the bi-channel structure with stacked Mg0.1ZnO0.9O (Mg= 10 at.%) and ZnO. The ZnO and Mg0.1Zn0.9O thin films were deposited by radio frequency (RF) co-sputter system onto the thermally oxidized silicon substrate. A total thickness of active layer was 50 nm. Firstly, the ZnO thin films were deposited to control the thickness from 5 nmto 30 nm. Sequentially, the Mg0.1Zn0.9O thin films were deposited to change from 45 nm to 20 nm. Thebi-layer TFT shows more improved properties than the single layer TFT. The field effect mobility and sub threshold slope for Mg0.1Zn0.9O/ZnO-TFT are 7.40 cm2V-1s-1 and 0.24 V/decade at the ZnO thickness of 10 nm, respectively.

Oxides possess several interesting properties, such as ferroelectricity, magnetism, superconductivity, and multiferroic behavior, which can effectively be used oxide electronics based on epitaxially grown heterostructures. The microscopic properties of oxide interfaces may have a strong impact on the electrical transport properties of these heterostructures. It was recently demonstrated that high electrical conductivity and mobility can be achieved in the system of an ultrathin LaAlO3 film deposited on a TiO2-terminated SrTiO3 substrate, which was a remarkable result because the conducting layer was at the interface between two insulators. In this study, we observe that the current-voltage characteristics exhibit LaAlO3 thickness dependence of electrical conductivity in TiO2-terminated SrTiO3. We find that the LaAlO3 layers with a thickness of up 3 unit cells, result in highly insulating interfaces, whereas those with thickness of 4 unit cells and above result in conducting interfaces.