Performance Evaluation and Reliability Issues of Junctionless CSG MOSFET for RFIC Design

This paper investigates the reliability issues of junctionless cylindrical surrounding-gate (JL CSG) MOSFET by employing temperature variations, ranging from 200 K to 500 K, along with the influence of interface trap charges. Furthermore, the analog/RF performance evaluation and linearity distortion analysis due to the interface trap charges in terms of figure-of-merit metrics, i.e., drain current I_ds; intrinsic gain (g_m/g_d) I_on/I_off ; cutoff frequency f_T; gain; gain transconductance frequency product; IMD3; VIP2; VIP3; IIP3; and higher order transconductance coefficients g_m1, g_m2, and g_m3 of JL CSG MOSFET have been carried out. A direct comparative study in terms of performance degradation is made between gate material engineered (GME) and single-material gate (SMG) JL CSG MOSFET using ATLAS 3-D device simulator. Simulation results reveal that a GME JL transistor shows better immunity against the influence of interface trap charges and exhibits significant enhancement to maintain device linearization, as compared to an SMG JL CSG MOSFET, so that it can be used as a high-efficiency linear radio-frequency integrated-circuit design and wireless applications. Also from simulation study, degrading effects in JL CSG MOSFET are more pronounce at low temperature and subthreshold region. Apart from analog/RF performance, trap charges change the temperature sensitivity coefficient of the drain current and zero crossover point.