Effect of La, Zr, co-doping on electrical properties of La-Zr-ZnO/n-Si(111) Schottky heterojunctions

Highlights: • The average grain size of La-Zr-ZnO films changes due to Zr ion doping. • Defective oxygen on the surface of La-Zr-ZnO films decreased. • La-Zr-ZnO films has two excitation peaks. • Rectification characteristics of La-Zr-ZnO/n-Si(111) schottky contact was enhanced. - Abstract: The La-Zr-ZnO/n-Si(111) schottky heterojunction was prepared by sol-gel method. The results showed that the average grain size of La-Zr-ZnO films decreases by increasing Zr ion doping concentration. Based on XPS analysis, it is found that O1s have been composed to two peaks, and the surface defect oxygen of La-Zr-ZnO films decreases. By the PL testing, La-Zr-ZnO films have two excitation peaks at 377.78 nm and 389.17 nm, respectively. As for La-Zr-ZnO/n-Si (111) schottky heterojunction, barrier height increased and ideality factor decreased with the increasing of La ion and Zr ion doping, indicating that the rectifying characteristics of ZnO/n-Si (111) schottky contacts was enhanced due to ion co-doping. It can be explained that oxygen vacancies of La-Zr-ZnO films decreases due to the ion doping and weakens Fermi level pinning.