Kinetic Theory Example
T = 300 °K [room temperature, at least if you like things toasty]
Nitrogen (N2 molecule), M = 28 gm/mole a = 3.7 Å
[the "growth rate" is the approximate amount of solid material that would be formed if each nitrogen molecule were incorporated into a solid on the surface -- shown here to demonstrate the very high growth rates that would be possible if every molecule was incorporated at high partial pressures of a precursor material]
Things to note:
- At 47,000 cm/second: a molecule will cross a 1-meter chamber in 2 msec -- about 1,000 miles/hour!
- The impingement-limited growth rate greatly exceeds actual growth rate. This means either the actual deposition precursor is rare (partial pressure at surface << total pressure) OR the probability of incorporation into the surface is small
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