No abstract

No abstract

With SCAP2D, a two-dimensional numerical code for silicon solar cells, we have explored the mechanisms controlling performance in high intensity high efficiency cells, focusing on the point contact cell for which record efficiencies have been reported. Our studies demonstrate that accurate Predictions of the intensity dependence of the short circuit current and open circuit voltage of these cells can be obtained by the inclusion of free carrier bandgap narrowing in the base and the reduction of the reported the Auger coefficient to be over four times the Dziewior and Schmid value [6-81. MODELING OF POINT CONTACT CELLSWe have examined with SCAP2D the steady-state short circuit current and open circuit voltage performance of two point contact cells reported by Sinton and Swanson, an 86 pm cell and a 240 pm cell [6,9]. minority carrier mobility in the base to approximately one-half the conventional value of Caughy and Thomas. In addition, the value for the ambipolar Auger coefficient by Dziewior and Schmid is retained, despite recent measurements which suggest it may be a factor of four larger than this. Band gap narrowing due to high injection conditions in the base may be another important limiting factor in silicon solar cells.