ABSTRACT Electronic devices are shrinking, and scanning transmission electron microscopy is essential for the characterization of in‐operando nanoscale devices. This paper demonstrates the combined capabilities of 4D‐STEM and STEM‐EBIC for measuring localized electronic properties (electric field strength, field direction, built‐in potential, and minority carrier diffusion length) in an in‐operando nanoscale device. Quantitative analysis supported by simulations enables robust interpretation of local electric fields and potential gradients. STEM‐EBIC measurements at different thicknesses show a regime where the effective diffusion length of minority carriers is entirely dominated by surface recombination. In situ biasing of a symmetrically doped 4 × 10 17 cm −3 p–n diode shows how 4D‐STEM and STEM‐EBIC complement each other for localized interpretation of electronic components.
Moynihan et al. (2026) studied this question.