Improvement of the minority carrier mobility in low-quality multicrystalline silicon using a porous silicon-based gettering under an O2 atmosphere

In this work we study the effect of O-2/porous silicon-based gettering on the electrical characteristics of low-quality multicrystalline silicon substrate. The gettering process is achieved by forming porous silicon (PS) layers on both sides of the wafers. The PS layers were formed by the stain-etching technique. The realized PS/Si/PS structure undergoes a heat treatment in an infrared furnace under an O-2 controlled atmosphere. PS damage is introduced like a simple sequence for efficient extrinsic gettering schemes. After the removal of the PS layer, gettering, effect was evaluated by measuring minority carrier lifetime which was performed using a WTC-120 photoconductance lifetime tester and dark I-V characteristics. As a result, an improvement of the minority carrier lifetime and dark I-V catecteristecs was observed. The gettering at 950 degrees C exhibits a more obvious effect on the increase in the short-circuit current density (J(sc)), open-circuit voltage (V-oc). (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of Organizers of European Materials Research Society (EMRS) Conference: Symposium on Advanced Inorganic Materials and Concepts for Photovoltaics.