Cathode sheath processes in a non-sputtering magnetron discharge

Abstract

The properties of cathode sheath in a non-sputtering magnetron discharge are discussed involving the theoretical assumptions based on the classical glow discharge description, and magnetron specific effects. It is shown that in a wide range of experimental conditions (gas pressure p from 1 to 100 Pa, discharge current Id from 10 to 1500 A), the trends for principal plasma parameters (electron density n and temperature Te) remain the same. Nevertheless, there is crucial difference in dominant supply of electrons between low pressure and elevated pressure non-sputtering magnetron regimes. Both secondary electron emission at low pressures and thermal ionization at high pressures result in sufficiently high electron source for sustaining dense non-sputtering magnetron plasmas at characteristically low voltage Vd ∼ 80–120 V.