Patent ID: 8895839

Claim:
A photovoltaic device, comprising a first doped silicon layer generated by irradiating a silicon surface with short radiation pulses while exposing the surface to a dopant, a second doped silicon layer forming a first junction with said first layer, and a third doped silicon layer forming a second junction with said second layer, each of said layers exhibiting an absorptance greater than about 60% for radiation in a different wavelength range of the solar spectrum so as to generate electron-hole pairs, wherein said first layer is capable of absorbing radiation at one or more wavelengths greater than about 1 micron with an absorptance greater than about 60%; and a transparent conductor layer adapted for exposure to external radiation, wherein said second doped silicon layer is capable of absorbing radiation at wavelengths in a range of about 0.7 microns to about 1.1 microns, and wherein said third doped silicon layer is capable of absorbing radiation at wavelengths in a range of about 0.25 microns to about 0.7 microns.