Electron energy probability function measurement in a 2 MHz and 13.56 MHz dual-frequency capacitively coupled argon plasma

Hong, Young-Hun; Kim, Tae Woo; Kim, Beom-Seok; Lee, Moo-Young; Chung, Chin-Wook

doi:10.1088/1361-6595/ac7ee2

Cited by 4 publications

(1 citation statement)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Here, τ LF is the period of the low-frequency (LF) bias source. P ohm and P stoc represent the Ohmic and stochastic heating power in the sheath, respectively [1,72].…”

Section: Sheath Modelmentioning

confidence: 99%

Investigation of the dual-frequency bias effect on inductively coupled Cl₂ plasmas by hybrid simulation

Tong

Zhao

Zhang

et al. 2023

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

In the etching process, a bias source is usually applied to the bottom electrode in inductively coupled plasmas (ICPs) to achieve independent control of the ion flux and ion energy. In this work, a hybrid model, which consists of a global model combined bi-directionally with a fluid sheath model, is employed to investigate the dual-frequency (DF) bias effect on the inductively coupled Cl2plasmas under different pressures. The results indicate that the DC self-bias voltage developed on the biased electrode is approximately a linear function of the phase shift between the fundamental frequency and its second harmonic, and the value only varies slightly with pressure. Therefore, the ion energy on the bottom electrode can be modulated efficiently by the bias voltage waveform, i.e., the fluctuation of the ion energy with phase shift is about 40% for all pressures investigated. Besides, the ion energy and angular distribution functions (IEADFs) in DF biased inductive discharges is complicated, i.e., the IEADFs exhibits a four-peak structure under certain phase shift values. Although the species densities and ion fluxes also evolve with phase shift, the fluctuations are less obvious, especially for Cl2+ ions at low pressure. In conclusion, the independent control of the ion energy and ion flux are realized in DF biased ICPs, and the results obtained in this work are of significant importance for improving the etching process.

show abstract

“…Here, τ LF is the period of the low-frequency (LF) bias source. P ohm and P stoc represent the Ohmic and stochastic heating power in the sheath, respectively [1,72].…”

Section: Sheath Modelmentioning

confidence: 99%

Investigation of the dual-frequency bias effect on inductively coupled Cl₂ plasmas by hybrid simulation

Tong

Zhao

Zhang

et al. 2023

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

show abstract

Effects of low-frequency voltage on nonlinear standing wave excitation, plasma uniformity, and ion dynamics in dual-frequency asymmetric capacitive discharges

Zhou,

Wen,

Liu

et al. 2024

Plasma Sources Sci. Technol.

View full text Add to dashboard Cite

It is known that in very-high-frequency capacitively coupled plasmas (VHF CCPs), the higher harmonics generated by nonlinear sheath motion can enhance the standing wave effect (SWE), which can lead to center-peaked plasma density profiles. In this work, an improved nonlinear electromagnetic model incorporating a transmission line model, an electron momentum balance model, a bulk plasma model, a collisionless nonlinear numerical sheath model, and an ion Monte-Carlo collision (MCC) model is developed to study the effects of low-frequency (LF) voltage VL on the nonlinear standing wave excitation, plasma uniformity, and ion energy and angular distribution functions (IEDFs and IADFs) in dual-frequency (DF) asymmetric capacitive argon discharges at relatively low pressure of 3 Pa. The plasma diffusion in the radial direction and ion dynamics within the LF oscillating sheath are self-consistently considered. The LF voltage VL at 2 MHz varies from 0 to 700 V while the high-frequency (HF) voltage VH at 60 MHz is fixed at 100 V. Simulation results indicate that without the addition of an LF source (i.e. VL = 0 V), there are a considerable number of high-order harmonics with short wavelengths, leading to significant SWE and central peak in the radial plasma density profile. Nevertheless, the high-order harmonic excitations tend to be weakened and merely occur around the phase of the full LF sheath collapse due to a shorter characteristic damping time of the surface waves as VL increases. This, combined with increased surface wavelengths of both the driving frequency and the higher harmonics at a higher VL, leads to suppressed standing waves and improved plasma uniformity. Meanwhile, the simulations show that both the low and the high energy peaks of IEDF move towards higher energies, and the energy peak separation width ΔE becomes wider with the increase of VL. The IEDF at the radial center of the powered electrode exhibits a broader ΔE than that at the edge. For the IADF, an increased VL results in more ions incident on the electrode with a smaller deflection angle. Because of a thinner sheath and a higher sheath voltage at the electrode center, the peak value of IADF at the electrode center is greater than that at the edge.

show abstract

Generation of high-density plasma via transparent electrode in capacitively coupled plasma

Moon,

Jung,

Park

et al. 2024

Plasma Sources Sci. Technol.

View full text Add to dashboard Cite

The effect of transparent capacitively coupled plasmas (TCCP) is investigated by using a transparent ITO electrode instead of the metal electrode of capacitively coupled plasmas (CCP). To compare CCP and TCCP, the CCP is made by coating the powered electrode with metal and the TCCP is made by coating the powered electrode with Indium Tin Oxide (ITO) on the quartz window. To compare the properties of electrodes based on ITO electrodes and metal electrodes in the same size reactor, electrode voltage, electron temperature and electron density were measured at various applied RF powers and pressures at 13.56 MHz. The electron temperature decreases overall with increasing pressure, regardless of the electrode type. We observed that the total voltage between the powered electrode and ground is about two times higher for the TCCP than for the CCP. In addition, the electron density of the TCCP increases significantly by about two times that of the CCP. In this TCCP, the voltage applied to the sheath is calculated based on the expectation that the increase in electron density is related to the voltage applied to the sheath. The results of calculating the voltage applied to each sheath of the CCP and the TCCP agree well with our expectations. In addition, we calculated the total power absorption per unit area and confirmed that the total power absorption per unit area is significantly higher in the TCCP than in the CCP.

show abstract

Electron energy probability function measurement in a 2 MHz and 13.56 MHz dual-frequency capacitively coupled argon plasma

Cited by 4 publications

References 58 publications

Investigation of the dual-frequency bias effect on inductively coupled Cl₂ plasmas by hybrid simulation

Investigation of the dual-frequency bias effect on inductively coupled Cl₂ plasmas by hybrid simulation

Effects of low-frequency voltage on nonlinear standing wave excitation, plasma uniformity, and ion dynamics in dual-frequency asymmetric capacitive discharges

Generation of high-density plasma via transparent electrode in capacitively coupled plasma

Contact Info

Product

Resources

About

Electron energy probability function measurement in a 2 MHz and 13.56 MHz dual-frequency capacitively coupled argon plasma

Cited by 4 publications

References 58 publications

Investigation of the dual-frequency bias effect on inductively coupled Cl2 plasmas by hybrid simulation

Investigation of the dual-frequency bias effect on inductively coupled Cl2 plasmas by hybrid simulation

Effects of low-frequency voltage on nonlinear standing wave excitation, plasma uniformity, and ion dynamics in dual-frequency asymmetric capacitive discharges

Generation of high-density plasma via transparent electrode in capacitively coupled plasma

Contact Info

Product

Resources

About

Investigation of the dual-frequency bias effect on inductively coupled Cl₂ plasmas by hybrid simulation

Investigation of the dual-frequency bias effect on inductively coupled Cl₂ plasmas by hybrid simulation