Polycrystalline Carbon: A Novel Material for Gate Electrodes in MOS Technology

Abstract

Polycrystalline carbon is proposed as a potential candidate for the gate material for submicron VLSI devices. Fine grained polycarbon films with significantly lower resistivity than polysilicon have been deposited on silicon dioxide. Well behaved capacitance-voltage and oxide breakdown characteristics are observed. Tunneling current measurements on these films indicate lower depletion effects in polycarbon compared to polysilicon. PMOSFETs have been fabricated with carbon gates in a conventional silicon process line to demonstrate the compatibility of polycrystalline carbon with existing silicon processes.