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Model for thickness dependence of radiation charging in MOS structuresThe model considers charge buildup in MOS structures due to hole trapping in the oxide and the creation of sheet charge at the silicon interface. The contribution of hole trapping causes the flatband voltage to increase with thickness in a manner in which square and cube dependences are limiting cases. Experimental measurements on samples covering a 200 - 1000 A range of oxide thickness are consistent with the model, using independently obtained values of hole-trapping parameters. An important finding of our experimental results is that a negative interface charge contribution due to surface states created during irradiation compensates most of the positive charge in the oxide at flatband. The tendency of the surface states to 'track' the positive charge buildup in the oxide, for all thicknesses, applies both in creation during irradiation and in annihilation during annealing. An explanation is proposed based on the common defect origin of hole traps and potential surface states.
Document ID
19770035201
Document Type
Reprint (Version printed in journal)
Authors
Viswanathan, C. R. (California, University Los Angeles, Calif., United States)
Maserjian, J. (California Institute of Technology, Jet Propulsion Laboratory, Pasadena Calif., United States)
Date Acquired
August 9, 2013
Publication Date
December 1, 1976
Subject Category
SOLID-STATE PHYSICS
Distribution Limits
Public
Copyright
Other