Even before ‘Black Silicon’ technology, based on IP developed by the National Renewable Energy Laboratory (NREL) and licensed to Natcore Technology, had reached commercialization, the technology will undergo a major material shift to reduce costs.
Reflecting the challenges of bringing new technology to the PV market during a phase of steep material price declines, NREL has expanded its license agreement with the start-up to use copper nanoparticles in the etching process instead of nanoparticles of gold or silver.
"Because copper is less expensive than the precious metals, this new patent could enable Natcore to further reduce the cost of solar cells," commented Natcore president and CEO Chuck Provini. "This could be another step toward our goal of halving the cost and increasing the output of solar cells."
Black silicon refers to the apparent colour of the surface of a silicon wafer after it has been etched with nano-scale pores; the black colour results from the virtual absence of reflected light from the porous wafer surface. NREL and Natcore scientist claimed a reflectance in the visible and near-infrared region of the solar spectrum of 0.3%, boosting conversion efficiencies.