Plasma dry etching for selective emitter formation in crystalline silicon based solar cell

Selective emitter formation in silicon based solar cell is recently becoming a common technique to enhance the blue response of solar cell. In this work, we suggest a novel procedure based on a self alignment thought to overcome the realignment problems that still limit its industrial request. The idea is based on a plasma dry etching procedure of the emitter region using the metal grid of the cell as a mask. In particular the plasma etching can reduce the thickness of a homogeneous heavily doped emitter reducing both doping concentration and sheet resistance. Since there is no necessity of realignment step in the proposed selective emitter fabrication process it can be useful and appealing for industrial PV manufacturing.