New Technique for Monitoring Nitrogen Ion Implantation Dose

Abstract

A new dosimetry technique for use in industrial nitrogen ion implantation is described. This relies on colour changes induced in anodized tantalum. Visual inspection of these dosimeters, by comparison with a set of calibrated standards, provides an accuracy of around ±20% over the range 1 × 10¹⁷-5 × 10¹⁷ nitrogen ions cm ⁻². Scope exists for more accurate use of the system by means of commercial colour analysis equipment. However, even as it stands, the material has been shown by field trials to be a useful accessory to commercial nitrogen ion implantation, i.e. for verifying applied dose, especially with complex workpiece geometries, and for evaluating implanter performance.