Structure and fabrication process for self-aligned locally deep-diffused emitter (salde) solar cell

The fabrication method and structure of a self-aligned locally deep-diffused emitter (salde) solar cell include the following parts a) a semiconductor substrate with first and second surfaces b) forming the first group emitter region on the first semiconductor substrate surface with smaller depth and lower dopand concentration c) forming the second group emitter region on the first semiconductor substrate surface with lager depth and higher dopand concentration than the first group emitter region, and the first and second group emitter regions locate on the first substrate surface alternately d) forming a doping region on the second semiconductor substrate surface to supply as the surface field e) forming a ohmic contact on the dopand region f) forming the first patterned ohmic layer including the forming of aluminum on the second group emitter region