Evaluation of properties of aluminum films deposited using an ultrahigh vacuum sputtering system

To explore the effects of residual impurity gases, such as H 2 O vapor and N 2 gas, in a sputtering environment on the crystallographic texture and grain sizes of Al-1%Si films, a quantitative study was carried out using an ultrahigh vacuum sputtering system. It was found that a small increase in the amount of H 2 O vapor in a sputtering environment reduced the growth of Al-Si film toward a (111) texture and also suppressed grain growth. In contrast, the residual N 2 gas has no indluence on the crystrallographic texture of the Al-Si film up to an N 2 partial pressure of 1.2 × 10 −3 Pa. These results indicate that a bakeable ultrahigh vacuum sputtering system with low-level residual H 2 O vapor is suitable for producing reliable aluminum interconnects.