Determination of Diffusion Length for the Finite Thickness Normal-Collector Configuration Using EBIC Technique

This paper presents a study of the extraction of the diffusion length in the normal-collector configuration with finite thickness with the use of the electron beam-induced current (EBIC) line scan. The EBIC data used were obtained from a commercially available device simulator. It was found that the surface recombination at the free surfaces affects the EBIC data, and therefore also affects the value of the extracted diffusion length and the linearization coefficient α. The effects of the surface recombination at the free surfaces and the sample thickness on the diffusion length extracted and the linearization coefficient α were researched and are discussed in this paper. Furthermore, the conditions at the free surfaces for a direct and accurate extraction of the bulk diffusion length at different sample thicknesses are suggested.