Interface Defect States and Charge Transport Properties in Low-Cost Photovoltaic Devices made from Scalable Deposition Methods

Electrochemical deposition and Atmospheric Atomic Layer Deposition (AALD) are high-throughput, scalable methods that can be used to produce low-cost transition metal oxides for photovoltaic devices. Previous work by our group has used electrochemical deposition to fabricate ZnO/Cu$_{2}$O cells, however the performance of these cells is limited by poor Cu$_{2}$O transport properties and recombination at interface states. AALD has been shown to produce much smoother films of Cu$_{2}$O but little work has been done to characterize the electrical properties of these films. Similarly little work has been done to show the ability of AALD to reduce interface defect states. In this investigation, we use impedance spectroscopy and illuminated solar cell performance to examine the electrical properties of Cu$_{2}$O films and ZnO/Cu$_{2}$O photovoltaic devices. We also show how AALD can deposit seed layers for further improved electrochemical deposition.