Modeling and simulation of the lateral photovoltage scanning method
- Farrell, Patricio
- Kayser, Stefan
- Rotundo, Nella
2010 Mathematics Subject Classification
- 35Q81 35K57 65N08
- Lateral-photovoltage-scanning method (LPS), semiconductor simulation, van Roosbroeck system, finite volume simulation, crystal growth
The fast, cheap and nondestructive lateral photovoltage scanning (LPS) method detects inhomogeneities in semiconductors crystals. The goal of this paper is to model and simulate this technique for a given doping profile. Our model is based on the semiconductor device equations combined with a nonlinear boundary condition, modelling a volt meter. To validate our 2D and 3D finite volume simulations, we use theory developed by Tauc  to derive three analytical predictions which our simulation results corroborate, even for anisotropic 2D and 3D meshes. Our code runs about two orders of magnitudes faster than earlier implementations based on commercial software . It also performs well for small doping concentrations which previously could not be simulated at all due to numerical instabilities. Our simulations provide experimentalists with reference laser powers for which meaningful voltages can still be measured. For higher laser power the screening effect does not allow this anymore.