The Study On The Reliability Of The Copper Interconnection In ULSI

The main purpose of the article is to study the reliability of copper interconnection. In many issues of the reliability of copper interconnection, we place the emphasis on electromigration and stress migration. Through the electromigration experiment, the electromigration resistance of copper interconnection with different width was compared, its MTF and activated energy was calculated, and the failure mechanism was explored. Then, difference between copper interconnection and aluminum interconnection was studied. Also, we simulated the electrical and mechanical characters of copper interconnection. The electrical simulation compared the temperature and the current density distribution in copper lines with different width and barrier materials, the result indicating that the maximum temperature locates in the middle of the line and the 20-degree obliquity is the most optimum one in the pore structure. The mechanical simulation compared the stress distribution in copper lines and pore, with the result that the maximum stress locates in the corner. In a word, copper interconnection has many advantages over aluminum interconnection. The reliability of the device with its implementation will be improved obviously.