Electron dynamics and SiO2 etching profile evolution in capacitive Ar/CHF3 discharges driven by sawtooth-tailored voltage waveforms

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Dong, Wan, Song, Liu-Qin, Zhang, Yi-Fan, Wang, Li, Song, Yuan-Hong, Schulze, Julian
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866915015861207040
author Dong, Wan
Song, Liu-Qin
Zhang, Yi-Fan
Wang, Li
Song, Yuan-Hong
Schulze, Julian
author_facet Dong, Wan
Song, Liu-Qin
Zhang, Yi-Fan
Wang, Li
Song, Yuan-Hong
Schulze, Julian
contents The electron dynamics and SiO2 etching profile evolution in capacitively coupled Ar/CHF3 plasmas driven by sawtooth-waveforms are investigated based on a one-dimensional fluid/Monte-Carlo (MC) model coupled with an etching profile evolution model. The effects of the sawtooth-waveforms synthesized from different numbers of consecutive harmonics, N, of a fundamental frequency of 13.56 MHz on the electron dynamics, ion and neutral transport, as well as the etching profile evolution are revealed in different mixtures of Ar/CHF3. By increasing N, a reduction in electronegativity, a decrease of the DC self-bias voltage, and a transition of the discharge mode from the Drift-Ambipolar (DA) to an α-DA hybrid mode is observed accompanied by an enhanced plasma asymmetry. As the CHF3 gas admixture increases, the electronegativity initially increases and then decreases, following a similar trend as the absolute value of the DC self-bias voltage. This is mainly caused by the change in ionization, attachment and de-attachment reaction rates. The obtained results show that placing the substrate on the grounded electrode and using a higher number of harmonic frequencies (N) can achieve a faster etching rate, since higher ion fluxes can be obtained in these scenarios. Additionally, the Ar/CHF3 gas mixing ratio impacts the neutral surface coverage, which in turn affects the etching rate. Therefore, selecting an appropriate gas mixture is also essential for optimizing etching results.
format Preprint
id arxiv_https___arxiv_org_abs_2411_07839
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Electron dynamics and SiO2 etching profile evolution in capacitive Ar/CHF3 discharges driven by sawtooth-tailored voltage waveforms
Dong, Wan
Song, Liu-Qin
Zhang, Yi-Fan
Wang, Li
Song, Yuan-Hong
Schulze, Julian
Plasma Physics
The electron dynamics and SiO2 etching profile evolution in capacitively coupled Ar/CHF3 plasmas driven by sawtooth-waveforms are investigated based on a one-dimensional fluid/Monte-Carlo (MC) model coupled with an etching profile evolution model. The effects of the sawtooth-waveforms synthesized from different numbers of consecutive harmonics, N, of a fundamental frequency of 13.56 MHz on the electron dynamics, ion and neutral transport, as well as the etching profile evolution are revealed in different mixtures of Ar/CHF3. By increasing N, a reduction in electronegativity, a decrease of the DC self-bias voltage, and a transition of the discharge mode from the Drift-Ambipolar (DA) to an α-DA hybrid mode is observed accompanied by an enhanced plasma asymmetry. As the CHF3 gas admixture increases, the electronegativity initially increases and then decreases, following a similar trend as the absolute value of the DC self-bias voltage. This is mainly caused by the change in ionization, attachment and de-attachment reaction rates. The obtained results show that placing the substrate on the grounded electrode and using a higher number of harmonic frequencies (N) can achieve a faster etching rate, since higher ion fluxes can be obtained in these scenarios. Additionally, the Ar/CHF3 gas mixing ratio impacts the neutral surface coverage, which in turn affects the etching rate. Therefore, selecting an appropriate gas mixture is also essential for optimizing etching results.
title Electron dynamics and SiO2 etching profile evolution in capacitive Ar/CHF3 discharges driven by sawtooth-tailored voltage waveforms
topic Plasma Physics
url https://arxiv.org/abs/2411.07839