SYSTEMS AND METHODS FOR MONOLITHICALLY ISLED SOLAR PHOTOVOLTAIC CELLS
The method for forming a monolithically isled solar cell comprises forming a first metal layer having base and emitter metallization on a passivated backside of a semiconductor substrate. An insulating support backplane is attached to a surface of the first metal layer and at least a portion of the semiconductor substrate passivated backside. Trenches are formed through the semiconductor substrate to the insulating support backplane in a trench isolation pattern partitioning the semiconductor substrate into a plurality of monolithically isled semiconductor regions. Vias are formed in the insulating support backplane to portions of the first metal layer base and emitter metallization. A second metal layer having base and emitter metallization is formed on the insulating support backplane. The second metal layer is electrically connected to portions of the first metal layer base and emitter metallization through the vias.
1 . A method for forming a monolithically isled solar cell, comprising:
forming a first metal layer on a passivated backside of a semiconductor substrate, said first metal layer having base and emitter metallization;
attaching an insulating support backplane to a surface of said first metal layer and at least a portion of said semiconductor substrate passivated backside;
forming trenches through said semiconductor substrate to said insulating support backplane in a trench isolation pattern, said trench isolation pattern partitioning said semiconductor substrate into a plurality of monolithically isled semiconductor regions;
forming vias in said insulating support backplane to portions of said first metal layer base and emitter metallization; and
forming a second metal layer having base and emitter metallization on said insulating support backplane, said second metal layer electrically connected to portions of said first metal layer base and emitter metallization through said vias.
2 . The method for forming a monolithically isled solar cell of claim 1 , wherein said step of attaching an insulating support backplane uses lamination.
3 . The method for forming a monolithically isled solar cell of claim 2 , wherein said insulating support backplane is a prepreg sheet.
4 . The method for forming a monolithically isled solar cell of claim 1 , wherein said step of forming trenches uses pulsed laser ablation.
5 . The method for forming a monolithically isled solar cell of claim 1 , wherein said step of forming trenches uses a combination of pulsed laser ablation and etching.
6 . The method for forming a monolithically isled solar cell of claim 1 , wherein said step of forming trenches uses mechanical scribing.
7 . The method for forming a monolithically isled solar cell of claim 1 , wherein said step of forming a first metal layer uses screen printing.
8 . The method for forming a monolithically isled solar cell of claim 1 , wherein said step of forming a first metal layer uses inkjet printing.
9 . The method for forming a monolithically isled solar cell of claim 7 , wherein said step of screen printing uses screen printing of a metal paste.
10 . The method for forming a monolithically isled solar cell of claim 1 , wherein said step of forming vias in said insulating support backplane uses laser drilling.
11 . The method for forming a monolithically isled solar cell of claim 1 , wherein said step of forming a second metal layer further comprises forming conductive vias using said second metal layer.
12 . The method for forming a monolithically isled solar cell of claim 1 , further comprising a step of depositing a conductive material in said vias.
13 . The method for forming a monolithically isled solar cell of claim 11 , wherein said step of depositing a conductive material in said vias uses a process chosen from the group consisting of stencil printing, inkjet printing, and screen printing.
14 . The method for forming a monolithically isled solar cell of claim 1 , wherein said step of forming a second metal layer uses a process chosen from the group consisting of physical vapor deposition, plating, screen printing, and inkjet printing.
15 . The method for forming a monolithically isled solar cell of claim 1 , wherein said step of forming a second metal layer uses physical vapor deposition followed by pulsed laser patterning.
16 . The method for forming a monolithically isled solar cell of claim 1 , wherein said step of forming a second metal layer uses physical vapor deposition followed by a combination of pulsed laser patterning and etching.
17 . The method for forming a monolithically isled solar cell of claim 1 , wherein said step of forming a second metal layer uses plating followed by a combination of pulsed laser patterning and etching.
18 . The method for forming a monolithically isled solar cell of claim 1 , wherein said step of forming a second metal layer uses deposition followed by a combination of inkjet print patterning and etching.
19 . The method for forming a monolithically isled solar cell of claim 1 , wherein said second metal layer comprises at least aluminum and a solderable capping layer.
20 . The method for forming a monolithically isled solar cell of claim 19 , wherein said capping layer comprises at least nickel or nickel vanadium.
21 . The method for forming a monolithically isled solar cell of claim 1 , wherein said second metal layer comprises at least copper and a solderable capping layer.
22 . The method for forming a monolithically isled solar cell of claim 21 , wherein said capping layer comprises at least tin.
23 . The method for forming a monolithically isled solar cell of claim 1 , wherein said semiconductor substrate is crystalline silicon.
24 . The method for forming a monolithically isled solar cell of claim 1 , further comprising frontside solar cell processing performed after at least said step of attaching an insulating support backplane.
25 . The method for forming a monolithically isled solar cell of claim 24 , further comprising frontside solar cell processing performed before at least said step of forming vias.
26 . The method for forming a monolithically isled solar cell of claim 24 , further comprising frontside solar cell processing performed after at least said step of forming a second metal layer.
27 . The method for forming a monolithically isled solar cell of claim 24 , wherein said frontside solar cell processing comprises at least passivating a frontside of said semiconductor substrate.
28 . The method for forming a monolithically isled solar cell of claim 1 , further comprising monolithically isled semiconductor regions thinning performed after at least said step of forming trenches through said semiconductor substrate to said insulating support backplane in a trench isolation pattern.
29 . The method for forming a monolithically isled solar cell of claim 1 , further comprising semiconductor substrate thinning performed after at least said step of attaching an insulating support backplane.
30 . The method for forming a monolithically isled solar cell of claim 1 , wherein said trench isolation pattern further partitions said semiconductor substrate into a plurality monolithically integrated bypass switches operating with said monolithically isled semiconductor regions.