Silicon oxide/silicon nitride dual-layer films: a stacked gate dielectric for the 21st century

Abstract

Incorporation of nitrogen atoms into ultra thin (<0.3 nm) gate dielectrics (i) reduces defect generation at the Si–SiO 2 interface, (ii) allows use of physically thicker dielectrics when incorporated into oxide–nitride stacked gate dielectrics, and (iii) prevents boron atom transport out of heavily doped p + polycrystalline silicon gate electrodes when nitrided layers are incorporated at the polycrystalline Si-dielectric interface. I demonstrate that nitrogen atoms can be selectively and independently incorporated into different parts of the gate dielectric structure by low-temperature (∼300°C) remote plasma assisted processing followed by low-thermal budget rapid thermal annealing (RTA) yielding state of the art field effect transistors with oxide equivalent thicknesses less than 2 nm.