Extraction of diffusion length using junction-less EBIC

The electron-beam-induced current (EBIC) mode of the scanning electron microscope (SEM) has been widely used in semiconductor materials and devices characterization in particular the extraction of minority carrier properties. The conventional approaches require the sample to have a built-in electric field created by the charge collecting junction that separates the majority carriers from the minority carriers and drives the induced current into the external circuitry for detection. As a result, these conventional approaches are not applicable for samples without junctions, i.e. bare substrates. This paper discusses the feasibility of extracting the minority carrier diffusion length in junction-less sample using the junction-less EBIC technique with the use of a two-point probe method. A 2-D device simulator is used to verify this technique and it is found the accuracy depends on the location of the origin.