Quantification of Secondary Electron Doping Contrast in the Scanning Electron Microscope on 4H-SiC

Abstract:

We discuss the quantification of the secondary electron doping contrast in the scanningelectron microscope on 4H-SiC. It has been observed and studied at length mostly on silicon, but noconclusive theoretical model has been proposed yet. Therefore, we propose a simple physical modelthat allows for a quantification of the doping contrast. It is based on the changes in effective ionizationenergy for different doping concentrations and types. For a better agreement between our model andthe experiment, a locally increased temperature of the electron system or separate quasi Fermi levelsfor electrons and holes have to be assumed. A line profile of the sample under investigation is comparedwith a SRIM simulation of the corresponding implant and shows very good agreement.

• Periodical: Materials Science Forum (Volume 1089)
• Pages: 23-29
• DOI: https://doi.org/10.4028/p-ike7kj
• Online since: May 2023
• Authors: Maximilian Moser*, Gregor Pobegen, Jürgen Smoliner
• Keywords: Doping Concentration, Doping Contrast, Gray Value, Physical Model, Quantification, Quasi Fermi Level Splitting, Scanning Electron Microscope, Secondary Electron

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