AVS 53rd International Symposium
    Plasma Science and Technology Thursday Sessions
       Session PS-ThP

Paper PS-ThP11
Anisotropic Deposition of Cu with a Plasma CVD Reactor Equipped with a High Power ICP H Source

Thursday, November 16, 2006, 5:30 pm, Room 3rd Floor Lobby

Session: High Pressure Discharges and Novel Diagnostics & Sources Poster Session
Presenter: S. Iwashita, Kyushu University, Japan
Authors: M. Shiratani, Kyushu University, Japan
J. Umetsu, Kyushu University, Japan
S. Iwashita, Kyushu University, Japan
K. Koga, Kyushu University, Japan
Correspondent: Click to Email
We have realized anisotropic deposition of Cu, for which Cu is filled preferentially from bottom of trenches without being deposited on their sidewall, by H-assisted plasma CVD.@footnote 1,2@ Such type of deposition has a potential to overcome common problems associated with conformal filling: namely, small crystal grain size below half of the trench width, and formation of a seam with residual impurities of relatively high concentration. A high flux of H atoms is required to deposit high purity Cu films at a high rate, because H irradiation to Cu films is effective in reducing impurities in the films. For this purpose, we have increased the maximum discharge power P@sub H@ of the ICP H source from 150 W to 1000 W. To obtain information about the H flux, we have examined dependence of optical emission intensity of H@alpha@(656 nm) on P@sub H@ as a parameter of a gas flow rate ratio R=H@sub 2@/(H@sub 2@+Ar). The following results are obtained in this study. 1) H@alpha@ intensity increases with P@sub H@. 2) H@alpha@ intensity is 10-100 times as high as that for our previous H source. 3) We have filled trenches completely with high purity Cu at a rate above several nm/min for R=11% using anisotropic deposition. Moreover deposition stops automatically just after filling trenches completely. @FootnoteText@ @footnote 1@K. Takenaka, et al., Pure. Appl. Chem. 77(2005)391.@footnote 2@K. Takenaka, et al., J. Vac. Sci. Technol. A22(4) (2004) 1903. .