Faculty Publications

Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736

Publications by NITK Faculty

Browse

Search Results

Now showing 1 - 3 of 3
  • Item
    Design of Dual-Material Gate Junctionless FinFET based on the Properties of Materials Forming Gate Electrode
    (Taylor and Francis Ltd., 2024) Mathew, S.; Bhat, K.N.; Nithin; Rao, R.
    This work elaborately investigates the electrical behaviour and short channel performance of Dual-Material Gate Junctionless Fin Field Effect Transistors (DMG-JLFinFETs) with multiple-gate metal pairs and varying gate metal length ratios. Rigorous analysis on the nature of DMG-JLFinFET with gate length as low as 10 nm is done using a device simulator by Silvaco, Inc. The gate material closer to the source, namely M1, has a dominating influence on the threshold voltage (Vth) and tunnelling current (Itunn) than the gate material closer to the drain (named M2) in a DMG-JLFinFET. Itunn is lower when the work function of M1 (ΦM1) is greater than the work function of M2 (ΦM2). The relative change in threshold voltage is minimum for Platinum–Gold (PtAu)-DMG-JLFinFET (0.68%). Titanium–Aluminium (TiAl) and Nickel–Titanium (NiTi) gate material pairs, having the same work function difference of 0.38 eV, have the least Drain-Induced Barrier Lowering (DIBL) of 12.88 mV/V. A better Sub-threshold Swing (SS) is observed for DMG-JLFinFET having ΦM1 < ΦM2. For devices with ΦM1 > ΦM2, SS can be improved by making a length of M1 (LM1) greater than 70% of the total gate length (Lg). © 2024 IETE.
  • Item
    Performance Enhancement of Dual Material Gate Junctionless FinFETs using Dielectric Spacer
    (Taylor and Francis Ltd., 2024) Mathew, S.; Bhat, K.N.; Nithin; Rao, R.
    In this work, a detailed investigation is done on the effectiveness of various spacer materials having different spacer lengths (LSP), in improving the performance of Dual-Material Gate-Junctionless FinFET (DMG-JLFinFET). Various performance metrics, such as Drain Induced Barrier Lowering (DIBL), Sub-threshold Swing (SS), ON current (ION), OFF current (IOFF), ratio of ION to IOFF (ION/IOFF), and tunneling current (Itunn), are closely monitored at gate lengths (Lg) down to 10 nm. DIBL degradation of 3.46 mV/V and SS degradation of 4.97 mV/dec are observed when Lg scales down from 30 nm to 10 nm. Except for the case of Itunn, other performance metrics improve with an increase in dielectric constant and length of spacer materials. The optimum performance of DMG-JLFinFET with a channel length of 10 nm is obtained when LSP is 5 nm. Enhancement in analog performance metrics is observed when high κ materials are used as spacers. Transconductance Generation Factor (TGF) improves from 35.86 V−1 to 47.4 V−1 and intrinsic gain increases from 6.93 dB to 11.98 dB when high κ dielectric materials like TiO2 are incorporated as spacers in a DMG-JLFinFET. © 2024 IETE.
  • Item
    An improved Fourier series-based analytical model for threshold voltage and sub-threshold swing in SOI junctionless FinFET
    (Elsevier Ltd, 2024) Mathew, S.; Chennamadhavuni, S.; Rao, R.
    In this work, Fourier series-based analytical models for threshold voltage (Vth) and Sub-threshold Swing (SS) are developed for Junctionless Fin Field Effect Transistor (JLFinFET) on Silicon On Insulator (SOI) substrate, taking into account the location of the onset of current conduction in the channel. Rigorous simulations were conducted to analyse the current conduction path when JLFinFET surpasses the threshold voltage. Based on the findings from these simulations, threshold voltage condition used for deriving the threshold voltage model is modified. This modified model gives a better prediction of Vth for JLFinFET than the already existing model which doesn't include approximations based on the location of onset of current conduction. The analytical model developed for SS is also capable of closely predicting the SS of JLFinFET obtained from the TCAD simulator down to a gate length of 20 nm. © 2024 Elsevier Ltd