The broader impact/commercial potential of the Small Business Innovation Research (SBIR) Phase I project is to demonstrate the feasibility of producing high-efficiency, low-cost, crystalline silicon photovoltaic solar cells without using silicon wafers. For the first time, additive manufacturing processes will be applied to silicon in order to produce equivalent performance to silicon wafers without the wasteful processes used in current manufacturing. If successful, this additive approach can link the parts of the solar supply chain that still exist in the United States?silicon refining and solar module assembly, establishing a full domestic supply chain for this critical energy technology. This supply chain can: (a) be built with off-the-shelf equipment at a third the cost of building traditional silicon wafer and cell factories, (b) cut the cost of photovoltaic solar cell manufacturing in half compared to imported silicon wafer-based solar cells, and (c) reduce energy consumption in solar cell manufacturing by 70% and reduce water consumption by 90%. This combination of low factory and production costs can drive the growth needed in the solar industry to support the nation?s decarbonization goals while creating tens of thousands of domestic jobs.This SBIR Phase I project seeks to demonstrate the feasibility of a novel architecture and additive manufacturing process for crystalline silicon photovoltaic solar cells that provide equivalent performance to traditional silicon wafer-based solar cells at lower cost with a local supply chain. The steps in the process flow are adapted from traditional solar cell processing or adjacent industries like microelectronics, but they are being combined in new way to realize this solar cell design. These steps will be co-optimized to produce high-efficiency cells using a series of designed experiments. These processes typically fall into three categories: (1) chemical or physical vapor deposition, (2) solution-based coating, and (3) thermal annealing, with their own relevant process variables: (a) time, temperature, pressure, gas flow rates, and magnetic power; (b) solvent, solution concentration, coating gap, and coating speed; (c) temperature vs. time. These process variables for each step will be correlated to physical properties of the layers in the cell stack such as thickness, stoichiometry, and performance of the finished cells to produce a prototype with performance that is compelling to investors, partners, and customers.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
