We have realized anisotropic deposition of Cu, for which Cu is filled preferentially from the bottom of trenches without being deposited on their sidewall, using H-assisted plasma chemical vapor deposition. The anisotropic deposition has two interesting features. One is the fact that the narrower the width of trench, the faster the deposition rate on its bottom becomes. The other is the self-limiting characteristic, that is the deposition in the trench stops automatically just after filling it completely. Such a 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. (C) 2004 American Vacuum Society.