Method for determination of neutral atomic oxygen flux

Abstract

A method for determining the flux of atomic oxygen atoms to a probe surface has been developed. Two probes are used. One is a glass probe enclosing a small, ceramic resistor heater and a thermocouple for determining the ambient local temperature. Another probe has a silver tip and inside it is only a thermocouple. In an atomic oxygen environment, such as a laboratory oxygen plasma, the silver probe will quickly develop a silver oxide coating which provides for atomic oxygen recombination. The temperature increase of the silver probe caused by energy release in the recombination reaction is matched by the glass probe using the resistive heater. The energy input to the glass probe allows determination of the atomic oxygen flux to the silver oxide probe. This is similar to other approaches using such probes except that by matching the temperature with a resistive heater in the glass probe, whose surface does not allow for recombination of atomic oxygen, a direct measure of the energy deposited on the silver probe may be obtained.