Multiscale simulation on plasma-surface interaction: mitigation of leakage current at high-k metal oxide interface

The miniaturization of silicon microelectronics demands a fine interface control on a gate dielectric in the MOSFET to mitigate undesirable gate leakage currents. In this paper, a multiscale simulation approach is proposed using atomistic simulations to examine the effect of the hydrogen plasma treatment (HPT) on high-k metal oxide/silicon interface. Molecular dynamics (MD) simulations are employed to understand the changes in the processing surface from the atomistic perspective. For varying processing conditions, atomic incident energy and substrate temperature, the evolutions of surface structural features including dangling bonds are thoroughly monitored. From the obtained surface structure after the hydrogen treatment, high-k metal oxide interface is modeled. Then, the localized electronic states within the energy band of the interfaces are examined with density functional theory (DFT), and the changes of interface traps due to HPT are discussed depending on the processing conditions. The present multiscale approach offers a possible way of understanding the influence of HPT on high-k metal oxide/silicon interface in terms of both structural and electrical perspectives.