Investigation of Morphology and Electrical Properties of Structures Based on the Heterojunction Monocrystalline Si/Microcrystalline ZnO

Abstract

The results of an experimental study of the surface morphology of zinc oxide films and the electrical properties of structures based on the monocrystalline Si/microcrystalline ZnO heterojunction are presented. The structure of zinc oxide films grown in an atmosphere of argon and oxygen is analyzed, and the size distribution of nanoscale fibers grown on its surface is obtained. The capacitance-voltage characteristics of the In/ZnO/n-Si/Al and Au/ ZnO/n-Si/Al heterostructures have been simulated. Based on the calculations and comparison of experimental and model dependences, the concentration of free charge carriers in the sample and the position of the Fermi level were determined, the presence of a fixed charge in the structure was revealed, the density of surface states was found based on the ratio of the voltage applied to the structure and the surface potential at the interface of the materials of the layers of structures. The value of the built-in surface charge is calculated. The interrelation of the upper contact material with the volt-farad and volt-ampere characteristics of the structure is investigated. The resistance of the formed zinc oxide films is calculated. The prevailing charge transfer mechanisms are discussed. The influence of technological modes of obtaining zinc oxide films obtained by spray pyrolysis on the structure of the surface, the effective capacity of the structure, the density of electronic states, the processes of charge carrier transfer in samples under the action of an electric field is analyzed.