High Energy Ion Implantation: Novel Approach on “as-implanted” Dose Control Concept

Abstract

Precise vertical doping profiles in the micrometer range are key components for drift layer formation of SiC-based high voltage power devices. In order to simplify multiple high-energy implantation sequences for creating high precision deep vertical doping profiles, recently the novel “energy filter” technology, which uses just one implantation step for complete profile formation, has been developed. An energy filter is a patterned silicon membrane, which transforms a high-energy monoenergetic ion beam into a beam with a pre-defined continuous range of ion energies, resulting in custom tailored deep impurity profiles. This approach poses new demands to ion dose monitoring, which, if not addressed properly, may limit MeV ion implantation application in wafer production. This work presents first results on concepts that are suited to provide fast and reliable implanted dose analysis, immediately after ion implantation in the several MeV range. High-energy ion implantation experiments were performed with and without energy filter, using different polymers as target materials and various implant doses. Target samples were analyzed in terms of their optical and geometrical properties changes. The results of the analysis, suggestions and limiting artefacts will be discussed.