Exploration of the impact of interface states density on the specific contact resistivity in TiSix/n+-Si Ohmic contacts through high-low frequency method. (13th June 2019)

• Record Type: Journal Article
• Authors: Zhang, Dan; Mao, Shujuan; Wang, Guilei; Xu, Jing; Luo, Xue; Zhao, Chao; Li, Junfeng; Wang, Wenwu; Chen, Dapeng; Ye, Tianchun; Luo, Jun
• Is Part Of: Japanese journal of applied physics. Volume 58:Number SH(2019)
• Publication Date: 2019-06-13
• Subjects: Physics -- Periodicals; 621.05
• DOI: 10.7567/1347-4065/ab1b64
• Languages: English
• ISSNs: 0021-4922

Abstract

Abstract: In our previous work, a reduction of specific contact resistivity ( ρ c ) in TiSi x /n + -Si Ohmic contacts by ∼21% has been achieved with proper Ge Pre-amorphization Implantation (PAI). In this work, the mechanism behind such an improvement using Ge PAI is explored experimentally. Versatile characterizations including current–voltage ( I– V ), capacitance–voltage ( C – V ) measurements and cross-sectional transmission electron microscopy (XTEM) are performed and analyzed. High-low frequency method is used to extract the responsive interface states density ( D it ) of TiSi x /n-Si Schottky diodes with and without Ge PAI. It is demonstrated that in TiSi x /n + -Si Ohmic contacts, the ρ c reduction by ∼21% with Ge PAI should be ascribed to the reduction of D it at TiSi x /n-Si interface. From the distribution of D it, it can be inferred that a part of shallow level defects can be annihilated after annealing for TiSi x /n-Si with Ge PAI, but deep level traps still exist. A further discussion about the relationship between D it and ρ c is tentatively provided.