Study on Effect of Neutral Gas Pressure on Plasma Characteristics in Capacitive RF Argon Glow Discharges at Low Pressure by Fluid Modeling

Continuum modelling of an asymmetric CCRF argon plasma reactor: Influence of higher excited states and sensitivity to model parameters

“…A decrease in the gas pressure ( p ) led to a lower electron density ( n e ) and thicker sheath regions. This is consistent with the observations of Samir et al, [ 17 ] who showed that sheath thickness and electron temperature ( T e ) in argon discharges are inversely proportional to p in the range of 0.1–1.5 Torr. The drop in T e from approximately 3.3 to 2.8 eV as pressure increased from 0.1 to 0.3 Torr is also consistent with experimental observations by Djerourou et al [ 4 ] and Cox et al, [ 27 ] who suggested that SEE and electron heating at the oscillating sheath boundary are enhanced at lower pressures, leading to higher T e .…”

“…The threshold energies for these grouped processes are listed in Table 2, and they were taken from the lowest threshold energy in the group. Superelastic collisions with electronically excited argon species are omitted in References [17,35,37,38] and included (typically for metastable species only) in References [12,13,30–33,36,39–41]. In the current study, superelastic collisions with excited species are only included for the metastable Ar m , using the principle of detailed balancing.…”

“…This is commonly seen for the metastable argon species 1 s 5 and 1 s 3 , [ 29 ] which are grouped as the metastable species Ar m . [ 12,13,30 ] Higher excited 2 p states (2 p 10 through 2 p 1 ) are often omitted from argon plasma models [ 9,17,31–34 ] ; however, they may also be grouped together with the metastable species [ 35–37 ] or represented as separate grouped processes. [ 30,38–41 ] The wide variability in choice of grouping, along with the cross‐section data chosen to represent these grouped processes, makes it difficult for readers to understand exactly which processes are represented in any given model.…”

“…The authors varied from 0.01 to 0.3 and showed that stronger SEE led to increases in electric field strength and electron temperature in the sheath, along with greater overall power absorption and electron density. The influence of gas pressure on electron energy transfer within an argon CCRF discharge was investigated by Samir et al [ 17 ] using a 1D model. The authors applied 100 V at 13.56 MHz while varying the pressure from 0.1 to 1.5 Torr, showing that higher pressures resulted in thinner sheaths and lower electron temperatures with peaks closer to the electrode boundaries, along with enhanced collisional power dissipation in the plasma and greater electron density.…”

Enhanced ionic wind generation by graphene for LED heat dissipation

“…Corona discharge technology is commonly used in industrial wastewater treatment, electrostatic precipitation, air purification, medical sterilization, food preservation, and heat transfer enhancement. It is especially attractive for locally enhanced heat dissipation in recent years, based on the principle of electrohydrodynamics (EHD), because it benefits from lower energy consumption and compact structure and is noiseless . The principle of enhanced heat transfer is that the corona discharge generates ionic wind, which creates a strong disturbance to the surrounding fluid, while generating an electrically induced secondary flow.…”