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Suprem-III User´s Manual
(synonym: )
The three oxidation model statements, DRYO2, WETO2, and NITROGEN, use identical parameters, differing
only in the values assigned. The parameters NIOX.C, NIOX.E, and NIOX.F are used in modeling the oxidation
of silicon nitride while the others deal with the oxidation of single and polycrystalline silicon.
The effects of chlorine in the ambient gas on the oxidation rate of silicon are currently modeled by an empirical
expression whose only variable is defined by the L.CLDEP and P.CLDEP for the linear and parabolic rates
respectively. To date no convenient function is available to calculate the chlorine dependence as a function of temperature
and amount of chlorine present, therefor a table of values defines the chlorine dependence factors at those
temperatures and percentages for which reliable data is available. For those temperatures and chlorine percentages
between the values in the table, linear interpolation is employed to calculate the value used. For temperatures or percentages
outside the range of values present in the table, the values whose conditions most nearly match the current
conditions are used. For example, if the current conditions are a temperature of 1175 degrees with three percent
chlorine, but the highest temperature entry in the table is 1150 degrees and the nearest chlorine percentages are for
two and four percent, then a value halfway between the values at 1150 degrees and two and four percent chlorine
will be used.