Langmuir Probe and Optical Emission Spectroscopy Studies of Low-Pressure Gas Mixture of CO2 and N2

摘要

Optical emission spectroscopy was used to study a gas mixture glow discharge of CO2 and N2 at a total pressure of 1.2 Torr, a power of 100 W and a flow of 16.5 L/min. The emission bands were measured in the wavelength range of 200 nm to 900 nm. The principal species observed were O2+ (A2∏u → X2∏g), CO+ (A2∏ → X2∑), N2+ (B2∑u+ → X2∑g+), CO2+ (A2∏ → X2∏), N2(C3∏u → B3∏g), O2(b1∑g+ → X3∑g-), and CO (a'3e → a3∏). The behavior of the band intensities as a function of the N2 percentage is consistent with recent Monte Carlo simulations. The electron temperature and ion density were determined by a double Langmuir probe. The electron temperature was found in the range of 1.55 eV to 2.93 eV, and the electron concentration in the order of 1010 cm-3. The electron temperature and ion density at pure N2 and pure CO2 agree with previous measurements.