Solar cell having a plurality of sub-cells coupled by cell level interconnection
Methods of fabricating solar cells having a plurality of sub-cells coupled by cell level interconnection, and the resulting solar cells, are described herein. In an example, a solar cell includes a plurality of sub-cells. Each of the plurality of sub-cells includes a singulated and physically separated semiconductor substrate portion. Each of the plurality of sub-cells includes an on-sub-cell metallization structure interconnecting emitter regions of the sub-cell. An inter-sub-cell metallization structure couples adjacent ones of the plurality of sub-cells. The inter-sub-cell metallization structure is different in composition from the on-sub-cell metallization structure.
1. A method of fabricating a solar cell, the method comprising:
forming a plurality of regions of a solder paste layer along a plurality of scribe regions of a semiconductor substrate;
subsequent to forming the plurality of regions of the solder paste layer, scribing the semiconductor substrate along the plurality of scribe regions of the semiconductor substrate to form a plurality of sub-cells each comprising a singulated and physically separated semiconductor substrate portion;
coupling adjacent ones of the plurality of sub-cells with a corresponding metal ribbon coupled to the solder paste layer at adjacent outer perimeters of corresponding adjacent ones of the plurality of sub-cells, wherein coupling adjacent ones of the plurality of sub-cells with the corresponding metal ribbon comprises coupling adjacent ones of the plurality of sub-cells with a metal ribbon comprising an intervening tab extending between the corresponding adjacent ones of the plurality of sub-cells; and
removing the intervening tab from the metal ribbon.
2. The method of claim 1 , further comprising:
forming a completed on-sub-cell metallization structure by forming a metal seed layer on each of the plurality of sub-cells.
3. The method of claim 1 , wherein scribing the semiconductor substrate along the plurality of scribe regions of the semiconductor substrate comprises performing a laser scribing process.
4. A method of fabricating a solar cell, the method comprising:
scribing a semiconductor substrate along a plurality of scribe regions of the semiconductor substrate to form a plurality of sub-cells each comprising a singulated and physically separated semiconductor substrate portion;
subsequent to scribing the semiconductor substrate, forming a plurality of regions of a solder paste layer at adjacent outer perimeters of corresponding adjacent ones of the plurality of sub-cells;
coupling adjacent ones of the plurality of sub-cells with a corresponding metal ribbon coupled to the solder paste layer, wherein coupling adjacent ones of the plurality of sub-cells with the corresponding metal ribbon comprises coupling adjacent ones of the plurality of sub-cells with a metal ribbon comprising an intervening tab extending between the corresponding adjacent ones of the plurality of sub-cells; and
removing the intervening tab from the metal ribbon.