Influence of Surface Preparation Prior to Thermal Nitridation on the Electrical Characteristics of Silicon Nitride Films Deposited on Polycrystalline Silicon Films

Abstract

ABSTRACTRapid thermal nitridation of the polycrystalline silicon film prior to the deposition of the silicon nitride dielectric film has been shown to be very effective in improving the dielectric characteristics for thin films. The changes at the polysilicon-silicon nitride interface has been further investigated using an in-situ clean process. This pre-treatment reduces the oxygen levels at the interface and improves the time dependent dielectric breakdown. The leakage current increases slightly due to the thinning of the silicon dioxide film at the interface.