Plasma discharge high-frequency

The multiple energetic collisions cause molecules to break apart, eventually to form only atoms, both charged and neutral. Insertion of sample molecules into a plasma discharge, which has an applied high-frequency electric field, causes the molecules to be rapidly broken down into electronically excited ions for all of the original component atoms. 

A discharge ignited in argon and coupled inductively to an external high-frequency electromagnetic field produces a plasma of ions, neutrals, and electrons with a temperature of about 7000 to 10,000°C. Samples introduced into the plasma under these extremely energetic conditions are fragmented into atoms and ions of their constituent elements. These ions are examined by a mass analyzer, frequently a quadrupole instrument. 

A glow-discharge (non-isothermal) plasma is generated in a gas by a high-frequency electric field, such as microwave (2.45 GHz), at relatively low pressure.P9] In such a plasma, the following events occur ... 

Like diamond, DLC can be obtained by CVD by plasma action in a hydrocarbon atmosphere. Its deposition process differs from that of diamond in as much as the activation is not so much chemical (i.e., the use of hydrogen atoms) but physical. This physical activation is usually obtained by colliding accelerated ions produced by a high-frequency discharge. 

Table 1. Energy content of various subsystems of the low pressure plasma. Example Nitrogen high frequency discharge, 27 MHz, p. D. = 1 Torr cm, I/D = 1 A cm-, degree of dissociation a 0.6, Tt = 873°K...

Current commercial plasma-enhanced CVD reactors operate with only two physical concepts. In one case, we have the inductively-excited discharge in a tube, which is used for plasma ashing of resist. The other is the parallel plate arrangement using high-frequency RF power to create a low-pressure glow discharge, where the wafers to be coated sit on one of the electrodes. 

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