DEVICE AND PROCESS FOR PRODUCING DC GLOW DISCHARGE

摘要

A device and process for producing a DC glow discharge at low pressure comprising a cylindrical stainless steel closed vacuum chamber (3) provided with means to create a low pressure in the range of 1X10<-5> to 5X10<-5> mbar preferably 1X10<-5> mbar, an open ended hollow cylindrical cathode (2) fixed near the one end of the said cylindrical stainless steel closed vacuum chamber at a predetermined distance from the said closed end of the said vaccum chamber by insulating means, a constricted anode (1) placed axially outside the said cylindrical cathode, a floating D.C. power supply to cylindrical cathode through a current limiting resistor and to the said constricted anode through a rectifier resulting in the emissions of the secondary electrons from the said cylindrical cathode by ion bombardement to travel along the electric field lines which are normal to the said hollow cylindrical cathode; introducing the media for creating the plasma in side the vacuum chamber to a pressure preferably at 10<-2> mbar to produce the DC glow inside the chamber followed by switching off the thermionic electron emitter once the plasma is produced. The plasma so generated breaks the atoms and molecules into ions and electrons, individual atoms and small collection of atoms (radicals) resulting in better nitriding, oxidizing, coatings, killing of micro-organisms and synthesizing powders.