Couplings in  semiconductors

The electronic transport in semiconductors is coupled to mechanical deformation through their effect on the electronic band structures. We are particularly interested in the consequences of this coupling on the electric response of deformable solar cells.

In a first theoretical work [Guin et al., 2018], we use thermodynamics to develop a fully-coupled model for deformable semiconductors. In particular, it captures the quasi-electric fields—resulting from nonuniform strains—that contribute to the flow of charge carriers.  We thereby model the effect of bending on the electric response of a solar cell.

In a second stage [Guin et al., 2020], we carry out experiments to measure the current-voltage characteristic of a crystalline silicon solar cell under uniaxial loading. Strain as low as 0.1% are related to change in the electric response by up to 3% thereby confirming the significant effect of deformations on the electric response.