The phenomena of excitons generation in the semiconductor such as silicon is observed when interaction between the electrons and the holes become high. This interaction is evidenced by a coupling coefficient denoted b. It takes values 10-15 cm3 .s-1 to 10-7 cm3 .s-1 according to the interaction level. In this article, there are studied the variation of excess excitons density in function to the doping level according to the two coupling model between electrons and excitons. This study shows that, near the junction between the base and the space charge region, the excess excitons density is very low. It decreases in function the doping level. Similarly, at the rear face, the higher excitons density in this area decreases as the doping level becomes important. A strong interaction between the charge carriers promotes the excitons generation.
