Temporal velocity distribution of positive and negative ions incident on a wafer in a pulsed two-frequency capacitively coupled plasma in CF 4/Ar for SiO2 etching

Takashi Yagisawa, Toshiaki Makabe

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

Two-frequency capacitively coupled plasmas (2f-CCP) are widely used for SiO2 etching. As the size of the element of the ultralarge scale integrated circuit (ULSI) decreases, a number of problems during plasma etching have been reported. In particular, charging damage caused by the difference of the velocity distribution between electrons and positive ions incident on an etched wafer will become an increasingly important issue. A pulse-modulated plasma with continuous-wave (CW) biasing at low frequency will become one of the practical solutions to the reduction of charging damage. In this paper, we numerically investigate the properties of the energy and angular distributions of positive and negative ions incident on a SiO2 wafer in a pulsed 2f-CCP system, which consists both of a very-high frequency (100 MHz) source for sustaining high density plasma and a low-frequency (1 MHz) bias for high-energy positive ions striking the wafer. The temporal behavior of the impact velocity distribution, which contributes to the reduction of the charges accumulated inside the hole/trench to be etched, are discussed for positive and negative ions.

Original languageEnglish
Pages (from-to)521-527
Number of pages7
JournalIEEE Transactions on Plasma Science
Volume31
Issue number4 II
DOIs
Publication statusPublished - 2003 Aug

Fingerprint

positive ions
negative ions
velocity distribution
etching
wafers
charging
low frequencies
damage
very high frequencies
impact velocity
sustaining
plasma etching
plasma density
continuous radiation
integrated circuits
energy distribution
angular distribution
pulses
ions
electrons

Keywords

  • CF/Ar
  • Ion velocity distribution (IVD)
  • Pulsed two-frequency capacitively coupled plasmas (2f-CCP)
  • SiO etching
  • Very-high frequency (VHF) (100 MHz)/LF(1 MHz) plasma
  • VicAddress

ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Condensed Matter Physics

Cite this

Temporal velocity distribution of positive and negative ions incident on a wafer in a pulsed two-frequency capacitively coupled plasma in CF 4/Ar for SiO2 etching. / Yagisawa, Takashi; Makabe, Toshiaki.

In: IEEE Transactions on Plasma Science, Vol. 31, No. 4 II, 08.2003, p. 521-527.

Research output: Contribution to journalArticle

@article{b8a408a531974e7c9888f7e8bded9b8f,
title = "Temporal velocity distribution of positive and negative ions incident on a wafer in a pulsed two-frequency capacitively coupled plasma in CF 4/Ar for SiO2 etching",
abstract = "Two-frequency capacitively coupled plasmas (2f-CCP) are widely used for SiO2 etching. As the size of the element of the ultralarge scale integrated circuit (ULSI) decreases, a number of problems during plasma etching have been reported. In particular, charging damage caused by the difference of the velocity distribution between electrons and positive ions incident on an etched wafer will become an increasingly important issue. A pulse-modulated plasma with continuous-wave (CW) biasing at low frequency will become one of the practical solutions to the reduction of charging damage. In this paper, we numerically investigate the properties of the energy and angular distributions of positive and negative ions incident on a SiO2 wafer in a pulsed 2f-CCP system, which consists both of a very-high frequency (100 MHz) source for sustaining high density plasma and a low-frequency (1 MHz) bias for high-energy positive ions striking the wafer. The temporal behavior of the impact velocity distribution, which contributes to the reduction of the charges accumulated inside the hole/trench to be etched, are discussed for positive and negative ions.",
keywords = "CF/Ar, Ion velocity distribution (IVD), Pulsed two-frequency capacitively coupled plasmas (2f-CCP), SiO etching, Very-high frequency (VHF) (100 MHz)/LF(1 MHz) plasma, VicAddress",
author = "Takashi Yagisawa and Toshiaki Makabe",
year = "2003",
month = "8",
doi = "10.1109/TPS.2003.815491",
language = "English",
volume = "31",
pages = "521--527",
journal = "IEEE Transactions on Plasma Science",
issn = "0093-3813",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
number = "4 II",

}

TY - JOUR

T1 - Temporal velocity distribution of positive and negative ions incident on a wafer in a pulsed two-frequency capacitively coupled plasma in CF 4/Ar for SiO2 etching

AU - Yagisawa, Takashi

AU - Makabe, Toshiaki

PY - 2003/8

Y1 - 2003/8

N2 - Two-frequency capacitively coupled plasmas (2f-CCP) are widely used for SiO2 etching. As the size of the element of the ultralarge scale integrated circuit (ULSI) decreases, a number of problems during plasma etching have been reported. In particular, charging damage caused by the difference of the velocity distribution between electrons and positive ions incident on an etched wafer will become an increasingly important issue. A pulse-modulated plasma with continuous-wave (CW) biasing at low frequency will become one of the practical solutions to the reduction of charging damage. In this paper, we numerically investigate the properties of the energy and angular distributions of positive and negative ions incident on a SiO2 wafer in a pulsed 2f-CCP system, which consists both of a very-high frequency (100 MHz) source for sustaining high density plasma and a low-frequency (1 MHz) bias for high-energy positive ions striking the wafer. The temporal behavior of the impact velocity distribution, which contributes to the reduction of the charges accumulated inside the hole/trench to be etched, are discussed for positive and negative ions.

AB - Two-frequency capacitively coupled plasmas (2f-CCP) are widely used for SiO2 etching. As the size of the element of the ultralarge scale integrated circuit (ULSI) decreases, a number of problems during plasma etching have been reported. In particular, charging damage caused by the difference of the velocity distribution between electrons and positive ions incident on an etched wafer will become an increasingly important issue. A pulse-modulated plasma with continuous-wave (CW) biasing at low frequency will become one of the practical solutions to the reduction of charging damage. In this paper, we numerically investigate the properties of the energy and angular distributions of positive and negative ions incident on a SiO2 wafer in a pulsed 2f-CCP system, which consists both of a very-high frequency (100 MHz) source for sustaining high density plasma and a low-frequency (1 MHz) bias for high-energy positive ions striking the wafer. The temporal behavior of the impact velocity distribution, which contributes to the reduction of the charges accumulated inside the hole/trench to be etched, are discussed for positive and negative ions.

KW - CF/Ar

KW - Ion velocity distribution (IVD)

KW - Pulsed two-frequency capacitively coupled plasmas (2f-CCP)

KW - SiO etching

KW - Very-high frequency (VHF) (100 MHz)/LF(1 MHz) plasma

KW - VicAddress

UR - http://www.scopus.com/inward/record.url?scp=0042929630&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0042929630&partnerID=8YFLogxK

U2 - 10.1109/TPS.2003.815491

DO - 10.1109/TPS.2003.815491

M3 - Article

VL - 31

SP - 521

EP - 527

JO - IEEE Transactions on Plasma Science

JF - IEEE Transactions on Plasma Science

SN - 0093-3813

IS - 4 II

ER -