Effect of bottom critical dimension (CD) size on TiN residual

Abstract

Abstract The relationship between bottom critical dimension (CD) size and TiN residual in semiconductor manufacturing was elucidated. As an excellent electrode material, TiN needs to be cut from the continuous TiN film during the capacitor preparation process to achieve parallel connection of capacitors and increase capacitance. However, TiN film may only partially be removed under different process conditions. To illustrate the reason for TiN residual and its relationship with bottom CD size, the TiN and oxide thin films were deposited by atomic layer deposition (ALD) and plasma enhanced chemical vapor deposition (PECVD), respectively. The results show that the amount of TiN residual and bottom CD size was strongly coupled when the bottom CD size larger than 140 nm TiN can be fully removed. However, if the trench bottom CD size is smaller than 85 nm, there are different degrees (residual TiN thickness within the various of 1.8-11 nm) of TiN remain. Therefore, the results of this paper are of much importance as a reference for process design.