Comparison Study for TiN Films Deposited from Different Method: Chemical Vapor Deposition and Atomic Layer Deposition

摘要

This paper compared two different film deposition processes for formation of TiN barrier layers, conventional TiCl_4-based chemical vapor deposition and atomic layer deposition (ALD). The 30nm thick TiN film deposited by conventional TiCl_4-based CVD at the process temperature of 600℃ followed by NH_3 post-deposition anneal showed about 180μΩcm of resistivity, over 95 % of step coverage for the pattern aspect ratio of 6 on 0.35+m contact diameters, and below 2 at.% of chlorine contents in the film. Meanwhile, the films deposited by ALD at 100℃ lower process temperature than CVD showed much better film properties even without post-deposition anneal. It showed lower resistivity values and lower chlorine incorporation along with better step coverage characteristics. More detailed material analysis was done by AFM, SEM, and AES.