Analysis of an anomalous hump in gate current after dynamic negative bias stress in HfxZr1-xO2/metal gate p-channel metal-oxide-semiconductor field-effect transistors

Abstract

"This letter investigates a hump in gate current after dynamic negative bias stress (NBS) in HfxZr1-xO2/metal gate p-channel metal-oxide-semiconductor field-effect transistors. By measuring gate current under initial through body floating and source/drain floating, it shows that hole current flows from source/drain. The fitting of gate current-gate voltage characteristic curve demonstrates that Frenkel-Poole mechanism dominates the conduction. Next, by fitting the gate current after dynamic NBS, in the order of Frenkel-Poole then tunneling, the Frenkel-Poole mechanism can be confirmed. These phenomena can be attributed to hole trapping in high-k bulk and the electric field formula Ehigh-k epsilon(high-k) = Q + E-sio2 epsilon(sio2). (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4739525]"