Electrochemical doping of porous silicon with rare earth element

Doping of rare earth element such as erbium into optical fibre to form light amplifier as been realised. It is also recognised that rare earth can provide a strong luminescence center for many materials. Conventional doping of rare earth elements in semiconductors is by ion implantation. Here we like to report that praseodymium has been successfully implanted into porous silicon using electrochemical method. This method is simple and potentially can be scaled up to industrial production. XPS analysis confirmed the presence of praseodymium in porous silicon. Strong electroluminescence was observed from the doped porous silicon. By varying the current density we have observed emission of spectra varied from red to green. The electroluminescence spectrum was similar to that of photoluminescence, except there was a distinct shoulder peak at the red-end of the electroluminescence spectrum.