High nitrogen atom yield downstream of an atmospheric pressure flowing Ar-N₂microwave discharge

A large yield of nitrogen atoms can be achieved at atmospheric pressure, from an Ar-N 2 surface-wave-induced microwave discharge with half the microwave power needed with a pure N 2 discharge. The dissociation of N 2 molecules into atomic nitrogen in this Ar-N 2 discharge is close to 22% at 0.3% N 2 concentration and decreases with increasing nitrogen concentration. The maximum nitrogen atom yield per watt is reached at 3% of N 2 . Such a low power and simple nitrogen atom source, with a typical flow rate of 10 l min -1 , is of interest for achieving metal nitriding at atmospheric pressure.