Investigation of Ni-based silicide formation by different dynamic surface annealing approaches

• Published in: 2010 18th International Conference on Advanced Thermal Processing of Semiconductors (RTP) pp. 76 - 78
• Main Authors: Yonggen He, Bing Wu, Guobin Yu, Jin Lin, Zhang, S, Jiong-Ping Lu, Jingang Wu, JiYue Tang, Ganming Zhao
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01.09.2010
• Subjects: Silicidation; Silicides
• ISBN: 9781424484003; 1424484006
• ISSN: 1944-0251; 1944-026X
• DOI: 10.1109/RTP.2010.5623785

Sub-melt millisecond anneal (MSA) is one of major anneal techniques for forming ultra-shallow and highly activated junctions. Besides post-implant anneal for source/drain and source/drain extensions, MSA has also attracted increased interests in nickel-silicide formation recently. During the silicidation process, desired Ni diffusion in forming silicides is competing with un-wanted Ni diffusion along defects paths. The latter will cause higher junction leakage and/or source/drain leakage. Since the activation energy for the un-wanted diffusion is lower, higher process temperature with shorter duration is beneficial for minimizing the un-wanted diffusion. Furthermore, MSA allows high process temperature to be used for silicide formation, which can re-activate some dopants, such as arsenic and phosphors. These dopants are easily deactivated during lower temperature thermal processes post source/drain formation such as silicide block film deposition; therefore, transistor performance can be improved by using MSA for silicidation processes. In this work, dynamic surface annealing (DSA), which is one form of MSA techniques, was applied to form Ni-based silicides. The impacts of different combinations of soak RTA and DSA for thermal steps before and after selective nickel/NiSi strip were examined. One step DSA has been demonstrated effective reduction of Nickel piping by e-beam inspection count, improved NiSi resistance and junction leakage w/o device performance degradation.