Short-channel effect improved by lateral channel-engineering in deep-submicronmeter MOSFET's

Abstract

The normal and reverse short-channel effect of LDD MOSFET's with lateral channel-engineering (pocket or halo implant) has been investigated. An analytical model is developed which can predict V th as a function of L e ; VDS; VBS, and pocket parameters down to 0.1-m channel length. The new model shows that the V th roll-up component due to pocket implant has an exponential dependence on channel length and is determined roughly by (Np) 1=4 Lp. The validity of the model is verified by both experimental data and two-dimensional (2-D) numerical simulation. On the basis of the model, a methodology to optimize the minimum channel length Lmin is presented. The theoretical optimal pocket implant performance is to achieve an Lmin approximately 5560% that of a uniform-channel MOS-FET without pocket implant, which is a significant (over one technology generation) improvement. The process design window of pocket implant is analyzed. The design tradeoff between the improvement of short-channel immunity and the other device electrical performance is also discussed. I. INTRODUCTION T HE REDUCTION of threshold voltage with decreasing channel length and increasing drain voltage is widely used as an indicator of the short-channel effect in evaluating CMOS technologies. This adverse roll-off effect is perhaps the most daunting road block in future MOSFET design. The device minimum acceptable channel length, , is primarily determined by the roll-off. The roll-off can be reduced or even reversed, i.e., the increases with decreasing channel length, by locally raising the channel doping next to the drain or drain/source junctions. The socalled Reverse Short-Channel Effect (RSCE) was originally observed in MOSFET's due to oxidation-enhanced-diffusion [1] or implant-damage-enhanced diffusion [2] which are very difficult to control. In the past few years, the locally high doping concentration in the channel near source/drain junctions has been implemented via lateral channel engineering,

Modeling and Simulation Investigation of Ferroelectric-Based Electrostatic Doping for Tunnelling Field-Effect Transistor

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Recent Progress in Two-Dimensional MoTe2 Hetero-Phase Homojunctions

“…Over the past few years, the complexity of integrated circuits (IC) in the semiconductor industry has increased with the decrease in the size of components [ 1 , 2 ]. However, traditional silicon-based transistors have been confronted with fundamental limits induced by quantum mechanics and thermodynamics at the nanometer scale [ 3 ], thereby leading to several problems, such as the short-channel effect [ 4 , 5 ] and severe carrier scattering by surface dangling bonds [ 6 , 7 ], which would degrade the device performance and hinder the scaling. To solve these problems, low-dimensional electronic materials including transition metal dichalcogenides (TMDs) have been intensively studied due to their prominent advantages, including atomically thin thickness without dangling bonds, diversity of bandgaps, and excellent performance that is superior to their silicon counterparts [ 8 ].…”

Self-aligned double injection-function contact mitigating short channel effects in sub-micron channels of solution processed indium gallium zinc oxide

“…Strategies for mitigating short channel effects can also be found in CMOS technology, but the approach consists of modifying the channel's edges and not of modifying the contacts. [21][22][23] Here, we suggest a new strategy which we term Double Injection Function (DIF) source electrode. The new source electrode design allows high ON current while reducing the short channel effects.…”