Printed silicon as diode and FET materials - Preliminary results

While polymers have been evaluated as the active layers in flexible electronics, the technical community is presently pursuing printed routes to inorganic semiconductors as a means of achieving higher mobilities. To utilize cost-effective polymeric substrates in a roll-to-roll manufacturing environment, low-temperature atmospheric-pressure deposition routes to semiconductors with reasonable electrical properties are required. In this talk, we will report the results of our initial investigations using cyclohexasilane (Si6H12)as a liquid precursor to amorphous silicon. Amorphous silicon (a-Si) films were prepared by spin-coating Si6H12 inks followed by various light and/or thermal treatments. Carrier properties of printed a-Si films prepared using undoped inks were determined by Hall probe. In addition, the results of various doping strategies for the formation of n-type and p-type a-Si layers led to heterojunction (i.e., heavily-doped Si wafer substrate) structures that exhibited field effect properties as well as multilayer devices that exhibited diode-type properties. Preliminary investigations indicate the possibility of generating 10 mu m wide lines of a-Si materials by collimated Aerosol Beam deposition Direct-Write (CAB-DW(TM)) of Si6H12-based inks. (C) 2008 Published by Elsevier B.V.