We found that
The first reaction is in equilibrium
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We found that |
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The first reaction is in equilibrium |
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Case A: Small Consumption of SIH2 |
In many cases a very thin film of the material is deposited
(a few molecular layers) and as a result very little SiH2 is
consumed. For example if SiH4 dissociates to form 1 mole SiH2
and 1 mole of H2 at equilibrium and then 0.01 mole of SiH2
is consumed in the deposition, then for all practical purposes  (i.e., 0.99 » 1.0). Consequently,
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| Case B: Significant Consumption of SIH2 |
One the other hand if significant amounts of SiH2
are consumed, we can still obtain  from the equilibrium relationship. However  and we must include  in the rate law |
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| which is the same as Eqn. below (S10-12) on p666. |
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