A New Highly Conductive Direct Gap p-Type Semiconductor La_1-YCuOS for Dual Applications: Transparent Electronics and...

The absence of a high-performance p-type transparent semiconductor still remains as a roadblock to the development of future generation optoelectronics. Here, a 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 a single phase is found to be 25%. By enhancing both the hole mobility and concentration of the LaCuOS phase, Y-substituted oxychalcogenide single-phase La_0.75Y_0.25CuOS 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 a band gap above 3 eV reported so far. The structural, electronic, and optical as well as the thermoelectric properties of La_1-YCuOS with a 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 a p-type La_0.75Y_0.25CuOS thin film and n-type Al-doped ZnO heterojunction with a high rectifying ratio of 300 is demonstrated, indicating its promising aspect for the next generation of invisible electronics and optoelectronics.