C-AFM and KPFM Characterization of poly-Si/SiOx/c-Si Passivated Contact Structure

Clément Marchat (1, 2) , Audrey Morisset (1, 2, 3) , J. Alvarez (1, 2) , Raphaël Cabal (3) , M.E. Gueunier-Farret (1) , J.P. Connolly (1) , Jean-Paul Kleider (1, 2)

1 GeePs - Laboratoire Génie électrique et électronique de Paris
2 IPVF - Institut Photovoltaïque d’Ile-de-France (UMR)
3 INES - Institut National de L'Energie Solaire

Poly-Si/SiOx/c-Si structures were characterized using conductive AFM (C-AFM) and Kelvin Probe Force Microscopy (KPFM) techniques with the objective to provide a better understanding of the structure, and notably the presence of nanoholes in the oxide. The observed samples include highly doped poly-Si layers annealed at different temperatures (700, 800 and 900 °C) and also intrinsic poly-Si layers. The latter layers have been in particular implemented to facilitate C-AFM and KPFM correlative analysis on the same scan areas. It is found that the C-AFM technique is not conclusive due to the high doping and surface morphology of the poly-Si layer. On the other hand KPFM allows to observe local surface potential drops that may be correlated to holes in the oxide. Correlative microscopy measurements applied on intrinsic poly-Si allowed to evidence links between C-AFM and KPFM observations, however surface conduction effects on c-AFM still remain.

Keywords: Photovoltaics; KPFM; c-AFM; pinhole; Diffusion

Domains: Physics [physics]; Condensed Matter [cond-mat]; Materials Science [cond-mat.mtrl-sci]; Engineering Sciences [physics]; Micro and nanotechnologies/Microelectronics; Engineering Sciences [physics]; Electric power; Engineering Sciences [physics]; Optics / Photonic; Engineering Sciences [physics]; Materials

Clément Marchat, Audrey Morisset, J. Alvarez, Raphaël Cabal, M.E. Gueunier-Farret, et al.. C-AFM and KPFM Characterization of poly-Si/SiOx/c-Si Passivated Contact Structure. 36th European Photovoltaic Solar Energy Conference and Exhibition, WIP, Sep 2019, Marseille, France. pp.22, ⟨10.4229/EUPVSEC20192019-1AO.2.6⟩. ⟨hal-02343908⟩