Fluorine Beam Performance of Fluoride Dopant Gases and Their Gas Mixtures

Fluorine co-implantation is used in advanced semiconductor device manufacturing for defect engineering, shallow junction formation, and material modification. A common setup for fluorine implantation includes feeding a fluoride dopant source gas into the ion source to provide fluorine (F) as one of the dissociation byproducts. Use of fluorine containing feed gases creates a halogen cycle which can negatively impact ion source performance, source life, implant tool productivity and cost of tool ownership. However, there has been a significant interest in improving fluorine ion beam performance considering its broad potential applications. This paper presents initial results of fluorine beam evaluation of common dopant candidates (BF₃, SiF₄ and GeF₄) and related hydrogen co-mixtures for added process efficiency and tool productivity improvements.