The influence of annealing environment of ZnO thin film on its photovoltaics performance

Abstract

One of the perspective types of solar cells are inverted organic solar cells (IOSCs) based on a bulk heterojunction (BHJ) [1]. However, the organic photoactive materials in these devices have a short exciton diffusion length and low charge carrier mobility, which reduces the performance of IOSCs. Therefore, to solve this problem, it is necessary to insert a buffer layer between the metallic electrodes and the active layer as a path for photogenerated carriers that are collected on the electrodes [2]. ZnO has unique properties such as excellent chemical and thermal stability in various ambient conditions, and also has in comparison with other metal oxides high electron mobility and high transparency in the visible wavelength range [3]. The development of methods for controlling the properties of ZnO using various technological treatments, such as annealing in air, inert atmosphere, oxygen rich environment and vacuum, which can change the properties of zinc oxide, is highly relevant. In this paper, we present the results of studying the electrical properties of ZnO films synthesized by the sol-gel method and the change in the properties of ZnO films during thermal annealing in various environments.