The Role of Secondary Electrons in Low Pressure rf GlowDischarge

We concerned on the role of secondary electrons in low pressure rf glow discharge. The Particle in Cell/Monte Carlo computer simulations (PIC/MC) was applied to simulate the discharge. The influence of secondary electron emission yield (SEY) on the plasma density was studied. Furthermore the relative density and the electron energy probability function of secondary particles, i.e., secondary electrons and the products of ionizing collisions of secondary electrons was determined. We found that the secondary particles play very important role in this type of discharge. The relative density of secondary electrons created on electrodes is 2-10%, 5-15% for the value of SEY = 0.1, 0.2 respectively. But due to the high electric intensity in electrode sheaths these electrons have relatively high energy and therefore they can ionize neutral atoms. As consequence of this the relative density of the secondary electrons (secondaries) and electrons created in ionizing collisions of the secondaries is more than 40% and the relative density of ions created in ionizing collisions of the secondaries is more than 20%, 40% for value of SEY = 0.1, 0.2, respectively.