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Generalized Model of Metal Bonding and Cleaning from Wafer Surfaces

Published online by Cambridge University Press:  21 February 2011

C. R. Helms  and
Heungsoo Park
C. R. Helms
Affiliation:
Department of Electrical Engineering, Stanford University, Stanford, CA 95305
Heungsoo Park
Affiliation:
Department of Electrical Engineering, Stanford University, Stanford, CA 95305
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Abstract

The removal of metals from the Si surface during aqueous cleaning is controlled by the thermodynamics of the metal ions dissolved in solution, the thermodynamics of the metal/Si surface complex, as well as the kinetics of the reactions taking place. In this paper we address one aspect of this problem: the thermodynamics of the metal/Si surface complex. We show that a number of cleaning effects can be explained by these considerations which involve the construction and application of metal/Si/oxygen ternary phase diagrams. Specifically, a class of metals with relatively unstable oxides, but stable silicides as shown by the phase diagrams are predicted to be difficult to remove from the Si surface; this prediction is born out by the available experimental data.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 315: Symposium Y – Surface Chemical Cleaning and Passivation for Semiconductor Processing , 1993 , 287
Copyright
Copyright © Materials Research Society 1993

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References

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