A DELTA-DOPED SUBSTRUCTURE IN SOLAR-CELLS - CARRIERS CONFINEMENT AND PHOTOCURRENT

This paper presents a modelling of the Low-High interfaces effects due to the implantation, in the emitter of a silicon solar cell, of a com plex structure consisting of a delta-doping profile coincident with a defect layer. It leads to analytical expressions of the potential barr iers and the drift electric fields due to these interfaces. The confin ement of the holes generated by the infrared absorption is studied. In parallel, we propose a numerical approach for the electric phenomena occurring in the cell emitter with a complex interface: it confirms ou r theoretical results. The electron photocurrent due to the normal abs orption is shown not to be altered by the complex structure. The hole confinement, near the front surface, can improve the performances of t he cell. Both our theoretical expressions and our numerical results pr edict this photocurrent increase.