A new highly conductive direct gap p-type semiconductor La1-xYxCuOS for dual applications: transparent electronics and thermoelectricity

The absence of high performance p-type transparent semiconductor still remains as a roadblock to the development of future generation optoelectronics. Here, highly conducting p-type transparent semiconductor based on Y incorporated LaCuOS oxychalcogenide is achieved for the first time, and the maximum Y substitution to obtain single phase is found to be 25%. By enhancing both the hole mobility and concentration of LaCuOS phase, Y substituted oxychalcogenide single phase La0.75Y0.25CuOS exhibits an outstanding p-type conductivity of 89.3 S.cm-1 with high optical transparency, which is the highest among all transparent oxychalcogenides with band gap above 3 eV reported so far. The structural, electronic and optical as well as the thermoelectric properties of La1-xYxCuOS with different Y substitution level are investigated, and the power factor was greatly enhanced to 4.322 μW m-1 K-2 after Y substitution. The highly performing diode based on p-type La0.75Y0.25CuOS thin film and n-type Al doped ZnO heterojun...