67th Annual Gaseous Electronics Conference
Volume 59, Number 16
Sunday–Friday, November 2–7, 2014;
Raleigh, North Carolina
Session ET2: Modeling of Plasma Etching
1:30 PM–3:00 PM,
Tuesday, November 4, 2014
Room: State C
Chair: Douglas Keil, Lam Research
Abstract ID: BAPS.2014.GEC.ET2.5
Abstract: ET2.00005 : Molecular dynamics analysis of silicon chloride ion incidence during Si etching in Cl-based plasmas: Effects of ion incident energy, angle, and neutral radical-to-ion flux ratio
2:45 PM–3:00 PM
Preview Abstract
Abstract
Authors:
Nobuya Nakazaki
(Kyoto University)
Koji Eriguchi
(Kyoto University)
Kouichi Ono
(Kyoto University)
Profile anomalies and surface roughness are critical issues to be resolved in plasma etching of nanometer-scale microelectronic devices, which in turn requires a better understanding of the effects of ion incident energy and angle on surface reaction kinetics. This paper presents a classical molecular dynamics (MD) simulation of Si(100) etching by energetic
Cl$_{x}^{+}$ ($x=$ 1--2) and SiCl$_{x}^{+}$ ($x=$ 0--4) ion beams with different incident energies $E_{\mathrm{i}}=$ 20--500 eV and angles $\theta_{\mathrm{i}}=$ 0--85$^{\circ}$, with and without low-energy neutral Cl radicals (neutral-to-ion flux ratios $\Gamma
_{\mathrm{n}}$/$\Gamma_{\mathrm{i}}=$ 0 and 100). An improved Stillinger-Weber interatomic potential was used for the Si/Cl system. Numerical results indicated that in Cl$^{+}$,
Cl$_{2}^{+}$, SiCl$_{3}^{+}$, and SiCl$_{4}^{+}$ incidences for $\theta
_{\mathrm{i}}=$ 0$^{\circ}$ and $\Gamma_{\mathrm{n}}$/$\Gamma _{\mathrm{i}}=$ 0, the etching occurs in the whole $E_{\mathrm{i}}$ range investigated; on the other hand, in SiCl$^{+}$ and
SiCl$_{2}^{+}$ incidences, the deposition occurs at low $E_{\mathrm{i}}$\textless 300 and 150 eV, respectively, while the etching occurs at further increased $E_{\mathrm{i}}$ [1]. For SiCl$^{+}$ and SiCl$_{2}^{+}$, the transition energies from deposition
and etching become lowered for $\Gamma_{\mathrm{n}}$/$\Gamma _{\mathrm{i}}=$ 100. Numerical results further indicated that in the SiCl$^{+}$ incidence for $\Gamma_{\mathrm{n}}$/$\Gamma
_{\mathrm{i}}=$ 0, the etching occurs in the whole $\theta _{\mathrm{i}}$ range investigated for $E_{\mathrm{i}}\ge $ 300 eV; on the other hand, for $E_{\mathrm{i}}=$ 100 and 150 eV, the deposition occurs at low $\theta_{\mathrm{i}}$\textless 60$^{\circ}$ and 40$^{\circ}$, respectively, while the
etching occurs at further increased $\theta_{\mathrm{i}}$; in addition, for $E_{\mathrm{i}}\le $ 50 eV, the deposition occurs in the whole $\theta_{\mathrm{i}}$ range investigated.\\[4pt]
[1] N. Nakazaki \textit{et al}., Jpn. J. Appl. Phys. \textbf{53}, 056201 (2014).
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2014.GEC.ET2.5