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The Effect of Roughness Features on Mos Surface Electric Field and Fowler-Nordheim Tunneling Behavior

Published online by Cambridge University Press:  10 February 2011

Heng-Chih Lin
Affiliation:
Department of Electrical Engineering, Stanford University, Palo Alto, CA94305
Edwin C. Kan
Affiliation:
Department of Electrical Engineering, Stanford University, Palo Alto, CA94305
Toshiaki Yamanaka
Affiliation:
Department of Electrical Engineering, Stanford University, Palo Alto, CA94305
Simon J. Fang
Affiliation:
Department of Electrical Engineering, Stanford University, Palo Alto, CA94305
Kwame N. Eason
Affiliation:
Department of Electrical Engineering, Stanford University, Palo Alto, CA94305
C. R. Helms
Affiliation:
Department of Electrical Engineering, Stanford University, Palo Alto, CA94305
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Abstract

For future CMOS GSI technology, Si/SiO2 interface micro-roughness becomes a non-negligible problem. Interface roughness causes fluctuations of the surface normal electric field, which, in turn, change the gate oxide Fowler-Nordheim tunneling behavior. In this research, we used a simple two-spheres model and a three-dimensional Laplace solver to simulate the electric field and the tunneling current in the oxide region. Our results show that both quantities are strong functions of roughness spatial wavelength, associated amplitude, and oxide thickness. We found that RMS roughness itself cannot fully characterize surface roughness and that roughness has a larger effect for thicker oxide in terms of surface electric field and tunneling behavior.

Type
Research Article
Copyright
Copyright © Materials Research Society 1997

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References

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