Experimental Investigation of As Preamorphization Implant on Electrical Property of Ti-Based Silicide Contacts

The impact of As preamorphization implant (PAI) on specific contact resistivity ( ρ _c ) is investigated for Ti-based Ohmic contacts on n ⁺ -Si in this article. The ρ _c value of TiSi _x /n ⁺ -Si contacts is greatly improved with low-dose As PAI whereas this improvement is impaired with increased dose of As PAI. The ρ _c results from the joint effort of the reduction of effective Schottky barrier height (SBH) to electrons ( φ _{\text bn,eff} ), retardation of Ti silicidation, and annihilation of end-of-range (EOR) defects. Besides, the interfacial microstructures of TiSi _x /n ⁺ -Si affect ρ _c , correlated with the post metal anneal (PMA).