TAILORING OF ELECTRON-ENERGY DISTRIBUTIONS IN LOW-TEMPERATURE PLASMAS

Assuming a background Maxwellian electron distribution we investigate the effects of tailoring the tail of the distribution upon the plasma density and electron temperature in a capacitive discharge. Taking the latter to be in the intermediate pressure regime the main effect of t he tail is to modify the rate coefficients for ionization and excitati on, and hence to alter the collisional energy loss per electron-ion pa ir created. We demonstrate that the background temperature can be supp ressed and the electron density increased by enhancing the tail popula tion. The model is applied to a typical set of low temperature conditi ons in argon and the changes in temperature and density calculated. In jecting 100 eV electrons into an argon plasma under very similar condi tions to those of the application of our model, the corresponding dens ities and temperatures are measured. Good qualitative agreement is fou nd.