Defect Current and Defect Band Conduction of Ultrathin Oxides after Degradation and Breakdown

Defect current of ultrathin oxides after degradation and breakdown was investigated by defect band structure model. The degradation and breakdown of SiO(2) can be modeled as a one dimensional linear chain of N identical defects with a effective Bohr radius a(d) separated by a distance R between electrodes. The degradation occurs when the defect distance ratio (rho = R/a(d)) local reaches a transition value of about 8 and defect potential barrier height (phi(DB)) approaches 1.1eV. Stress-induced leakage current (SILC) occurs, if rho >= 8 or q phi(DB) = 1.1eV; soft breakdown (SBD) occurs, if 0.27eV <= q phi(DB)<1.1eV or 3.8 <= rho < 8; and hard breakdown (HBD) occurs when q phi(DB) =0 or rho = 3.4. The huge defect current differences between SILC, SBD, and HBD are solely due to different defect distance.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000265971000064&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Engineering, Electrical & ElectronicPhysics, AppliedEICPCI-S(ISTP)