The Improvement of Immunity to Electromigration by Means of Microstructural Design

It is known from literature that the properties of thin films greatly depend on their structuare. Therefore, the microstructural design is attractive for control over the properties of thin metal films used for interconnect metallization.In this paper we discuss the potentialities of the self-ion assisted deposition technique for control over the grain and grain boundary structures of thin metal films and their properties such as resistivity and immunity to electromigration.It was found that resistivity of aluminum films deposited at the 6 kV bias was virtually equal to resistivity of bulk aluminum. Films deposited at the less bias or without it had higher resistivities. Abnormal grain growth was found in 6 kV-films. In films prepared without bias normal grain growth proceeds.