Diagnostics of RG argon discharge
- Univ. of Bombay (India)
- B.A.R.C., Bombay (India)
A system was set up for the study of Radio frequency assisted dc Glow (RG) Discharge Cleaning technique. The system had a high degree of versatility, that is, a number of parameters could be varied and adjusted for the evaluation of the efficiency of the GDC technique. The main discharge chamber is a cylinder of SS 304 having 10 cm dia, 50 cm length and having various ports on it. A turbomolecular pumping unit is used to evacuate it to a base pressure of 1 x 10{sup -7} mbar. The argon gas is introduced through the leak valve so that the pressure in the desired range is obtained. In the RG mode the rf power at 13.56 MHz was coupled to the plasma by inductive coupling. The rf electrode was made of stainless steel coil having inductance 1.1 {mu}H. Connections to this coil were made through tm 35 mm (OD) flanges with proper ceramic to metal feedthroughs. One end of the coil was connected to rf ground via a 10 nF capacitor. Other end of the coil vas connected through the impedance matching network to the rf power supply. This end of the coil was also connected to a dc supply (5 KV ) via a decoupling inductor (2 H) and 10 K/100 W resistor in series. In case of rf discharge a SS rod was introduced along the axis of the chamber. In dc glow discharge a hollow cathode configuration was used. The discharge chamber itself was grounded cathode and the anode was in the form of SS 304 plate. The Langmuir double probe, consisting of tungsten wire of 0.1 cm dia and length 1.2 cm, is inserted through a feedthrough and located centrally within the discharge. Proper rf filtering and compensation are required to eliminate rf interference which distorts the characteristics. To minimize the rf voltage across the probe sheath, we adopted the tuned Langmuir probe technique. The probe characteristics, have been analysed an the basis of theories which assume no collisions between electrons and positive ions before they are collected by the probe.
- OSTI ID:
- 212860
- Report Number(s):
- CONF-950749-; TRN: 96:010029
- Resource Relation:
- Conference: 22. international conference on phenomena in ionized gases, Hoboken, NJ (United States), 31 Jul - 4 Aug 1995; Other Information: PBD: 1995; Related Information: Is Part Of XXII International conference on phenomena in ionized gases. Contributed papers 2; Becker, K.H.; Carr, W.E.; Kunhardt, E.E. [eds.]; PB: 226 p.
- Country of Publication:
- United States
- Language:
- English
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