The extraction of the surface recombination velocity of Si:P emitters using advanced silicon models
The recombination velocity S of minority carriers at the surface of phosphorus doped emitters is re-extracted from published measurements of the emitter saturation current-density J(ind oe), by means of numerical simulations. In contrast to previous studies, Fermi-Dirac statistics and a quantum mechanically derived band gap narrowing model are used (instead of Boltzmann statistics and empirical apparent BGN data). In this way, degeneracy effects are accounted for on a physically sounder basis. The new model reproduces the measured J(ind oe) values of highly-doped emitters with mctal-covered surfaces (where S is known). Due to this newly achieved self-consistency, emitters with dopant densities higher than 3x10(exp 19) cm-3 are simulated considerably more precisely than in the past.