A New Quantum Effect in Metal-Oxide-Semiconductor Field-Effect Transistor: Threshold Voltage Creep with Gate Voltage

Abstract

We report a new quantum effect in metal-oxide-semiconductor field-effect transistor (MOSFET), namely that the twodimensional (2-D) inversion charge falls substantially short of the classically predicted linear increase with gate voltage (V G ) in strong inversion. This effect is to be effectively quantified via the threshold voltage (V TH ) increasing with V G in the classical current-voltage (I-V) model and is called herein the threshold voltage creep (VTH-creep). In 0.18 m MOSFET, for example, VTH-creep amounts to 58% of the V TH at the device turn-on point, when V G is swept from 0.5 to 2 V. Additionally, the VTHcreep significantly affects the extraction of effective mobility ( eff ) from the I-V data. VTH-creep is shown a key to the accurate I-V modeling and constitutes one of the most clearly observed quantum phenomena in MOSFET.

Low-Frequency Noise Assessment for Deep Submicrometer CMOS Technology Nodes

“…45,46 This affects important electrical quantities like the intrinsic carrier concentration or the inversion layer charge density, which become smaller than the classical ones. 39,47 The lifting of the degeneracy of the conduction band minima also drastically changes the cross section ( 2D ) of an interface trap for the capture of a carrier from a two-dimensional ͑2D͒ electron gas, compared with the one for the classical 3D band structure ( 3D ). 48 As recently shown in more detail, 39 2D is a strong function of the vertical electric field, closely following the dependence of the input-referred noise spectral density on V GS .…”