Abstract

Chemical vapor deposition is uniquely suited for depositing metal films with characteristic dimensions ranging from nanometers to meters. The general utility of the method has been limited by the difficulty in controlling film purity for many metals, however, largely because of the complexities of gas-surface interactions as the films grow. There have been a number of studies addressing the surface chemistry of metal CVD for the aluminum alkyls, Cu(I) and Cu(II) complexes, Cr, Mo, W, Ni and Fe carbonyls and WF₆.¹ Most of this work has focussed on monolayer-level chemistry rather than deposition under steady-state gas flow at typical CVD pressures, so knowledge of factors affecting surface reactions leading to decomposition is still somewhat limited. In particular, the relationship between surface reactions and gas transport is essentially unexplored although it is a critical aspect of scaling of the chemistry with feature dimensions. This issue has received some attention in modelling of direct write deposition rates,² although reaction mechanisms were not considered.

© 1997 Optical Society of America