Solexel, SunPower-Backed Thin Silicon Startup, Gets $14.8M in VC
Solexel is hoping to mass produce 35-micron-thick, high-performance, low-cost mono-crystalline solar cells using a lift-off technology based on a reusable template and a porous silicon substrate. According to the company's claims, the process ensures that the thin silicon is supported during handling and processing while the back contact, p-type cell dispenses with the need for expensive silver, using aluminum instead. The process uses no wet steps, according to the CEO, Michael Wingert, and employs CVD on trichlorosilane gas at atmospheric pressure with silicon deposited at a rate of 2.5 microns per minute. The cell uses almost ten times less silicon than conventional c-Si cells, at about 0.5 grams per watt.