Effect of La incorporation on reliability characteristics of metal-oxide-semiconductor capacitors with hafnium based high-k dielectrics

Metal-oxide-semiconductor (MOS) devices with various concentrations of La incorporation in Hf based dielectrics were characterized to evaluate the effect of La on device performance and reliability. La incorporation does not increase charge trapping centers while it is effective in modulating V-FB. The lifetime from dielectric breakdown improved as the La incorporation increases. Progressive breakdown behavior gradually disappears as La incorporation increases. Since charge trapping under a bias stress gets worse as La incorporation increases, a process optimization is required to simultaneously improve the charge trapping and dielectric breakdown. (C) 2011 Elsevier B.V All rights reserved.