Silicon-doped carbon semiconductor from rice husk char

The aim of this work is to prepare semiconductor grade carbon from the agricultural residue, rice husk. Rice husk on pyrolysis in a fixed bed reactor produces solid char which when mixed with metallic magnesium powder at a certain ratio and being heated in a closed steel tube reactor at a high temperature results in formation of silicon-doped carbon. The resistivity vs. temperature characteristics shows that material is semiconducting in nature. Suitable doping with phosphorous and boron results in n- and p-type characteristics in the silicon-doped carbon. The electronic parameters of the material are evaluated using Hall measurement technique and four-probe method. The I–V characteristic of a p–n junction prepared by suitable doping of the silicon-doped carbon shows a current ramp in the forward direction and a sharp rise in reverse current like a diode. The method of production of such semiconductor material can generate a new avenue for semiconductor industry.