KPFM surface photovoltage measurement and numerical simulation

Clément Marchat (1, 2) , James P Connolly (2) , Jean-Paul Kleider (2, 1) , José Alvarez (2, 1) , Lejo Koduvelikulathu (3) , Jean Baptiste Puel (4, 1)

1 IPVF - Institut Photovoltaïque d’Ile-de-France (UMR)
2 GeePs - Laboratoire Génie électrique et électronique de Paris
3 ISE Konstanz e.V. - International Solar Energy Research Center
4 EDF R&D - EDF R&D

A method for the analysis of Kelvin probe force microscopy (KPFM) characterization of semiconductor devices is presented. It enables evaluation of the influence of defective surface layers. The model is validated by analysing experimental KPFM measurements on crystalline silicon samples of contact potential difference (V CPD) in the dark and under illumination, and hence the surface photovoltage (SPV). It is shown that the model phenomenologically explains the observed KPFM measurements. It reproduces the magnitude of SPV characterization as a function of incident light power in terms of a defect density assuming Gaussian defect distribution in the semiconductor bandgap. This allows an estimation of defect densities in surface layers of semiconductors and therefore increased exploitation of KPFM data.

Domaines: Science des matériaux [cond-mat.mtrl-sci]; Micro et nanotechnologies/Microélectronique; Energie électrique; Optique / photonique; Matériaux

Clément Marchat, James P Connolly, Jean-Paul Kleider, José Alvarez, Lejo Koduvelikulathu, et al.. KPFM surface photovoltage measurement and numerical simulation. EPJ Photovoltaics, 2019, 10, pp.3. ⟨10.1051/epjpv/2019002⟩. ⟨hal-02308439⟩