Coupled Point Defect and Impurity Diffusion Model for OED/ORD <BR>(Model OED)



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Coupled Point Defect and Impurity Diffusion Model for OED/ORD
(Model OED)

 

Accurate impurity diffusion simulation under oxidizing conditions demands the simultaneous simulation of point defects and impurities. Diffusion equations are solved for the silicon self-interstitials and vacancies . In (3.2-32) the symbols , and denote the diffusion coefficients for interstitials and vacancies and the bulk recombination constant (Frenkel-pair mechanism), respectively.

 

As boundary conditions at the interface we assume surface recombination for interstitials and vacancies, and an interstitial generation to be proportional to the oxidation rate (3.2-33), (3.2-34).

 

 

is the atomic density of silicon (), and are the surface recombination velocities for interstitials and vacancies, respectively, and determines the fraction of consumed silicon atoms which is injected into the substrate.

The boundary conditions for the impurity atoms are the same as in the analytical model. The implemented parameter values are summarized in Table 3.2-6. The values for interstitials are from Bronner and Plummer [Bro87], values for vacancies are from Tan and Gösele [Tan85].

 



Martin Stiftinger
Wed Oct 19 13:03:34 MET 1994