Flat-band voltage and low-field mobility analysis of junctionless transistors under low-temperature

Abstract

This paper presents the low-temperature characteristics of flat-band (V-FB) and low-field mobility in accumulation regime (mu(0_acc)) of n-type junctionless transistors (JLTs). To this end, split capacitance-to-voltage (C-V), dual gate coupling and low-temperature measurements were carried out to systematically investigate V-FB. Additionally, the gate oxide capacitance per unit area C-ox and the doping concentration N-D were evaluated as well. Accounting for the position of V-FB and the charge based analytical model of JLTs, bulk mobility (mu(B)) and mu(0_acc) were separately extracted in volume and surface conduction regime, respectively. Finally, the role of neutral scattering defects was found the most limiting factor concerning the degradation of mu(B) and mu(0_acc) with gate length in planar and tri-gate nanowire JLTs.