HIGH EFFICIENCY SINGLE CRYSTAL SILICON SOLAR CELL WITH EPITAXIALLY DEPOSITED SILICON LAYERS WITH DEEP JUNCTION(S)

摘要

Embodiments of the present invention may include single crystal silicon solar cell structures with epitaxially deposited silicon device layers with deep junction(s). In some embodiments, the single crystal silicon solar cell structures may comprise a moderately doped, thick (greater than 10 microns), epitaxially deposited silicon emitter layer. In some embodiments, the single crystal silicon solar cell structures may comprise moderately doped, thick (greater than 10 microns), epitaxially deposited FSF layers. The moderate doping reduces electron-hole recombination within the FSF and emitter layers and causes smaller bandgap narrowing and reduced Auger recombination compared to prior art devices which typically have more heavily doped layers, and the thicker FSF and emitter layers than typically used in prior art devices assist in having a desirable sheet resistance for the solar cell front and back surface, as measured prior to front side and back side metallization.

主权项

1. A silicon solar cell structure comprising:
an n-type single crystal epitaxial silicon layer, said n-type single crystal epitaxial silicon layer having an n-type dopant concentration in the range of intrinsic to 1.0E16/cm3, endpoints inclusive, said n-type single crystal epitaxial silicon layer having first and second surfaces; and a front surface field (FSF) on said second surface of said n-type single crystal epitaxial silicon layer, said FSF comprising a diffused layer having an n-type dopant concentration in the range of 1.0E17/cm3 to 5.0E20/cm3, endpoints inclusive, wherein said diffused layer has a thickness in the range of 0 to 5 microns; and a p+ emitter on said first surface of said n-type single crystal epitaxial silicon layer, said p+ emitter comprising an as-deposited p-type single crystal epitaxial silicon layer with a p-type dopant concentration in the range of 1.0E16/cm3 to 5.0E18/cm3, endpoints inclusive, said p+ emitter further comprising an aluminum-doped p-type single crystal epitaxial silicon layer separated from said first surface by said as-deposited p-type single crystal epitaxial silicon layer, said as-deposited p-type single crystal epitaxial silicon layer having an average thickness in the range of 10 microns to 60 microns, endpoints inclusive.