Development of (111) Al texture grown on Ti and TiN underlayer for electromigration lifetime improvement

Abstract

The effects of underlayer texture on Al texture development and of Al texture on electromigration resistance were investigated. We have found that Al (111) texture can be enhanced by the control of Ti and TiN underlayer textures. Values of full width at half maximum for Al (111) rocking curves ranged from 0.64 deg. to 4.7 deg. for Al-Cu films grown on Ti, TiN/Ti, and Ti/TiN/Ti underlayers. Al (111) texture and TiN (111) texture were improved consecutively deposited on Ti underlayers with (10⋅0) preferred orientation for Al/Ti and Al/TiN/Ti, resulting in electromigration lifetime improvement.