In situ computerized optical reflectivity measurement system for ion implantation

A computerized in situ optical reflectivity measurement system for the quantitative determination of material parameter changes of a substrate during the process of ion implantation is presented. These changes are related to the extent and nature of the induced crystal disorder in the substrate. The system consists of an optical reflectometer, with data acquisition and signal processing capabilities. For each sample a case history of the implant is obtained in the form of a continuous graph of reflectivity vs. a desired implantation parameter (e.g. dose). Examples regarding the implantation of ³¹P⁺ , ⁴⁰Ar⁺, and ¹⁴N⁺ are presented. Additional suggestions for further system development and applications are made. Among the advantages of in situ measurements are the time-effort-expense. savings, a higher yield of experimental data per sample, higher accuracy, repeatability, and various possibilities of process control