Silicon based photon-enhanced thermionic emission devices

Silicon has been widely used in semiconductor industry for decades. This gives rise to the availability of cost-effective materials and a wide range of processing tools and knowhow. The band gap of silicon is also fairly optimal for harvesting solar energy. In fact, the most of the photovoltaic devices manufactured nowadays are based on silicon. Therefore, silicon would also be a good candidate for photon-enhanced thermionic emission (PETE) solar cells. We investigate the use of silicon as the cathode material in PETE cells. The investigation is based on our previously published model and experimental results obtained from surface-science measurements in an ultra-high vacuum setup. The model takes into account both front and back side surface recombination, the Shockley-Read-Hall (SRH), Auger, and radiative recombination in the bulk as well as the temperature dependence of the band gap, donor ionization, absorption coefficient, and charge carrier mobilities. Our results indicate the PETE effect in silicon, thus further supporting use of silicon in PETE based solar power.