SiOnyx And “Black Silicon”  

XConomy reports on a technique for increasing the efficiency of solar panels using "black silicon" - SiOnyx Brings “Black Silicon” into the Light; Material Could Upend Solar, Imaging Industries

Silicon is a wonderfully cooperative element. It takes relatively little energy to promote the electrons in a silicon crystal from their usual, docile orbits around the atomic nuclei into wild, free circulation. That’s what makes silicon a semiconductor—valuable for electronic switching devices such as transistors, sensing devices such as the CCDs in cameras and X-ray machines, and energy-generating devices such as photovoltaic cells.

But silicon would be more wondrous if it were even more responsive—if an incoming photon needed less energy to knock loose an electron, for example, or if a single photon could kick loose many electrons. In pursuit of this vision, chemists, physicists, and engineers have spent decades trying out various ways of modifying silicon crystals—for example, by doping them with atoms of arsenic or other elements that put more free electrons into the mix.

Almost ten years ago, graduate students in the laboratory of physics professor Eric Mazur at Harvard University stumbled across a new way of making silicon more responsive: they found that if they blasted the surface of a silicon wafer with an incredibly brief pulse of laser energy in the presence of gaseous sulfur and other dopants, the resulting material—which they called “black silicon”—was much better at absorbing photons and releasing electrons. And this week, after nearly three years in hyper-stealth mode, a spinoff company with an exclusive license from Harvard to commercialize the process has begun talking with reporters.

Executives for the company, called SiOnyx, believe that its technology will help semiconductor manufacturers build far more sensitive detectors and far more efficient photovoltaic cells, using essentially the same silicon-based processes they currently depend on—thereby revolutionizing areas such as medical imaging, digital photography, and solar energy generation.