SBIR Phase II: Spray Deposited Transparent Conducting Zinc Oxide Films

This Small Business Innovation Research (SBIR) Phase II project seeks to develop a cost-effective, non-vacuum technology to deposit p-type transparent conducting oxide (TCO) films. The lack of effective p-type TCOs has been a long-standing problem for the electro-optic industry. It is the crucial component to advance photovoltaic technology with n-type absorbers. The Phase I project developed cutting-edge spray pyrolysis technology to deposit wide-gap p-zinc oxide (p-ZnO) films. The project achieved important breakthroughs, both in terms of the new deposition system, as well as achieving p-ZnO films with inexpensive spray pyrolysis. The structural and electro-optical data for the ZnO films validate the feasibility of the new deposition approach and provide a compelling measure of project success. The Phase II project will advance the deposition system, improve the scientific understanding of doping issues, derive process-property correlations to optimize the electro-optical properties, and integrate technology into existing technology. The broader impact/commercial potential for new optoelectronic products is increasing exponentially, owing to the demand for clean energy and the microelectronics revolution. The deposition method offers cost and manufacturability advantages over current vacuum methods; it is remarkably versatile to deposit a number of other technological semiconductors that are amenable to spray deposition. The p-ZnO films can be used for short-wavelength light-emitting diodes, laser diodes, energy efficient windows, flat panel displays, gas sensors and other opto-electronic applications. It can extend photovoltaic technology to n-type absorbers and multi-junction flexible solar cells for higher efficiency. The commercialization of this technology will provide energy security, avert future power crises and reduce global warming.