Solar Cell Device Physics, 2nd Edition

APPENDIX E

The Quasi-neutral-region Assumption and Lifetime Semiconductors

Figure E.1 Classification of materials by electrical resistivities. Here ρ is the resistivity in the units of ohm-cm. For this figure, the material permittivity ε has been taken to be 10−12 F/cm and the carrier lifetime τn,p has been taken to be 10−8 s. The ranges noted on the figure shift according to permittivity and lifetime values.

In our analytical treatment of the mathematical systems describing solar cell behavior, we are forced to make the assumption that certain regions of the cell structure can be considered to be quasi-neutral even in the presence of current ...