MOS transistors with stacked SiO/sub 2/-Ta/sub 2/O/sub 5/-SiO/sub 2/ gate dielectrics for giga-scale integration of CMOS technologies
- 1 November 1998
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Electron Device Letters
- Vol. 19 (11) , 423-425
- https://doi.org/10.1109/55.728900
Abstract
Advances in lithography and thinner SiO/sub 2/ gate oxides have enabled the scaling of MOS technologies to sub-0.25-/spl mu/m feature size. High dielectric constant materials, such as Ta/sub 2/O/sub 5/, have been suggested as a substitute for SiO/sub 2/ as the gate material beyond t/sub ox//spl ap/25 /spl Aring/. However, the Si-Ta/sub 2/O/sub 5/ material system suffers from unacceptable levels of bulk fixed charge, high density of interface trap states, and low silicon interface carrier mobility. In this paper we present a solution to these issues through a novel synthesis of a thermally grown SiO/sub 2/(10 /spl Aring/)-Ta/sub 2/O/sub 5/ (MOCVD-50 /spl Aring/)-SiO/sub 2/ (LPCVD-5 /spl Aring/) stacked dielectric. Transistors fabricated using this stacked gate dielectric exhibit excellent subthreshold behaviour, saturation characteristics, and drive currents.Keywords
This publication has 16 references indexed in Scilit:
- New methodologies for measuring film thickness, coverage, and topographyIEEE Transactions on Magnetics, 2000
- Fabrication and characterization of Si-MOSFET's with PECVD amorphous Ta2O5 gate insulatorIEEE Electron Device Letters, 1997
- Use of carbon-free Ta2O5 thin-films as a gate insulatorMicroelectronic Engineering, 1997
- MOSFET transistors fabricated with high permitivity TiO/sub 2/ dielectricsIEEE Transactions on Electron Devices, 1997
- Leakage current reduction in chemical-vapor-deposited Ta2O5 films by rapid thermal annealing in N2OIEEE Electron Device Letters, 1996
- Current drive enhancement by using high-permittivity gate insulator in SOI MOSFET's and its limitationIEEE Transactions on Electron Devices, 1996
- A Two-Step, Lightly Nitrided Gate Oxidation Process For Sub-0.5 μm Cmos TechnologyMRS Proceedings, 1996
- Extended x-ray absorption fine structure analysis of the difference in local structure of tantalum oxide capacitor films produced by various annealing methodsApplied Physics Letters, 1995
- Surface cleaning effect on dielectric integrity for ultrathin oxynitrides grown in N2OApplied Physics Letters, 1994
- High electric fields in silicon dioxide produced by corona chargingJournal of Applied Physics, 1973