AVS 53rd International Symposium
    Plasma Science and Technology Monday Sessions
       Session PS1-MoM

Paper PS1-MoM6
Plasma and Etching Characteristics for C@sub 6@F@sub 6@ Gas

Monday, November 13, 2006, 9:40 am, Room 2009

Session: Etch for Advanced Interconnect I
Presenter: S.C. Park, Samsung Electronics, Korea
Authors: S.C. Park, Samsung Electronics, Korea
H.S. Shin, Samsung Electronics, Korea
J.W. Sun, Samsung Electronics, Korea
C. Shin, Samsung Electronics, Korea
C.-J. Kang, Samsung Electronics, Korea
H. Cho, Samsung Electronics, Korea
J.-T. Moon, Samsung Electronics, Korea
M.S. Kim, Air Products and Chemicals, Inc.
B. Ji, Air Products and Chemicals, Inc.
W.J. Howard, Air Products and Chemicals, Inc.
Correspondent: Click to Email
In this paper for studying plasma and etching characteristics of C@sub 6@F@sub 6@, we chose C@sub 6@F@sub 6@ as one of the promising candidates of next generation high aspect-ratio contact(HARC) etching gas because it could make more polymer than C@sub 4@F@sub 8@ and C@sub 4@F@sub 6@ which widely used as HARC etching gas. High polymer generation characteristic could resolve the selectivity problem which has become more serious in sub-100nm HARC etching. To identify the difference between C@sub 6@F@sub 6@ and other gases, plasma and etching characteristics were compared. Quadrupole mass spectroscopy(QMS) and optical emission spectroscopy(OES) were used to identify plasma characteristics and X-ray photoelectron spectroscopy(XPS) was used to investigate the polymer from each gases. Gases were used for sub-100nm HARC etching and etching characteristics were compared. Commercial CCP-type etcher was used for etching. C@sub 6@F@sub 6@ showed 1.7 times higher polymer deposition rate than C@sub 4@F@sub 8@, but it showed lower C/F ratio in polymer than other gases contrary to higher C/F ratio in the gas. This C/F ratio in polymer affected profile and selectivity during HARC etching. From QMS study, we knew that C@sub 6@F@sub 6@ cracked into relatively larger molecules than other gases at the same condition, and CF@sub 2@@super +@ ion was not observed from C@sub 6@F@sub 6@ cracking patterns as we could expect from C@sub 6@F@sub 6@ gas structure. This fragment patterns also affected polymer composition and etching characteristics. We used C@sub 6@F@sub 6@ to etch sub-100nm HARC etching and compared with other gases.