SBIR-STTR Award

Researchers Bryon Larson and Obadiah Reid (National Renewable Energy Laboratory and C.U. Boulder, respectively) have developed a type of steady-state microwave photoconductance machine (patent pending) that allows them to monitor the quality of perovskites solar cells (PSCs), and Tau Science is interested in licensing and commercializing this technology. PSCs represent a new class of low cost, high performance thin film solar cell, and the rapid improvements in performance and stability suggest that prototype manufacturing lines will soon begin to proliferate as worldwide production begins to ramp. Various substrates may be used for PSCs including glass, stainless steel and even flexible plastic depending upon the application. To support this industry shift, the test and measurement industry will need to develop quality control techniques that are suitable for large scale roll-to-roll processing lines and tailored to the particular properties of PSCs. This project includes developing a compact version of the NREL prototype and testing several strategies to improve upon the original system’s signal to noise ratio. A nine-month Phase 1 R&D effort will allow us to design, build and characterize the miniature system for both perovskites and current-generation CdTe modules. During this time, we will evaluate the technology’s industry readiness, begin working with potential commercial partners and identify required design modifications before the next round of development. In Phase 2 we plan to develop a beta-site machine that will be installed at a commercial manufacturing site for testing and feedback. The PSC industry growth is expected to be rapid and this presents new opportunities for US companies, favoring those with a sustainable technical advantage.Tau Science plans to file additional patents as the technique is developed and modified, in addition to those that may be awarded to the originators of the technique.

Next-generation solar cells are being developed by researchers around the US and the world, but they lack a key component- measurement systems that can control the factories of tomorrow. A patent-pending machine was developed at NREL to do just that, and Tau is partnering with both NREL and University of Toledo to bring the machine to market. The technique uses a variable-wavelength light source and microwave reflectometer to measure the quality of thin-film semiconductor materials at a high rate- and keep up with the roll-to-roll deposition systems that are being developed in industry. In Phase I, Tau Science developed a compact prototype and found, during testing at NREL, that it met the goal of ~500x improvement in sensitivity relative to the original machine. This will be the starting point for our Phase II work, in which we will expand the capabilities into time-resolved and wavelength-resolved models that can provide even more information for process control in future PV factories. In Phase II, scientists from U. Toledo and NREL will generate samples to intentionally test the sensitivity of the technique to common processing problems, and will work with Tau Science to improve the machine until it is ready to deliver to the first US commercial customer in 2023.