SYSTEMS AND METHODS FOR MONOLITHICALLY ISLED SOLAR PHOTOVOLTAIC CELLS
The monolithically isled solar cell comprises a semiconductor layer having a light receiving frontside and a passivated backside opposite the frontside. A first metal layer on the semiconductor layer passivated backside comprises base and emitter metallization islands corresponding to monolithic isled semiconductor regions. An insulating support backplane is attached to the first metal layer and portions of the semiconductor layer passivated backside. Trenches formed through the semiconductor layer to the insulating support backplane in a trench isolation pattern electrically isolate the semiconductor layer into monolithic isled semiconductor regions arranged on the insulating support backplane. Conductive vias through the insulating support backplane contact portions of each of the first metal layer base and emitter metallization islands. A second metal layer base and emitter metallization on the insulating support backplane contacts the first metal layer base and emitter metallization islands. The second metal layer electrically interconnects the monolithic isled semiconductor regions.
1 . A monolithic isled solar cell, comprising:
a semiconductor layer with a background doping and having a sunlight-receiving frontside and a passivated backside opposite said sunlight-receiving frontside;
a first metal layer on said semiconductor layer passivated backside, said first metal layer having at least one base and emitter metallization island for each of a plurality of monolithic isled semiconductor regions;
an insulating support backplane attached to a surface of said first metal layer and at least a portion of said semiconductor layer passivated backside;
trenches formed through said semiconductor layer to said insulating support backplane in a trench isolation pattern, said trench isolation pattern electrically isolating said semiconductor layer into said plurality of monolithic isled semiconductor regions having said background doping of said semiconductor layer;
said plurality of monolithic isled semiconductor regions arranged on said insulating support backplane according to said trench isolation pattern;
conductive vias through said insulating support backplane to portions of said first metal layer base and emitter metallization islands; and
a second metal layer having base and emitter metallization on said insulating support backplane and contacting said first metal layer base and emitter metallization islands by said conductive vias, said second metal layer electrically interconnecting said plurality of monolithic isled semiconductor regions.
2 . The monolithic isled solar cell of claim 1 , wherein said second metal layer interconnects at least two of said plurality of monolithic isled semiconductor regions in series to increase the solar cell voltage and decrease the solar cell current.
3 . The monolithic isled solar cell of claim 1 , wherein said conductive vias and said second metal layer are the same material.
4 . The monolithic isled solar cell of claim 1 , wherein said trench isolation pattern has a trench planar surface area less than 2% of the area of said semiconductor layer.
5 . The monolithic isled solar cell of claim 1 , wherein said trenches have a trench width less than 1000 μm.
6 . The monolithic isled solar cell of claim 1 , wherein said second metal layer comprises at least a material chosen from the group consisting of copper and aluminum.
7 . The monolithic isled solar cell of claim 1 , wherein an interdigitated metallization pattern of said second metal layer is arranged orthogonally to an interdigitated metallization pattern of said first metal layer.
8 . The monolithic isled solar cell of claim 1 , wherein an interdigitated metallization pattern of said second metal layer comprises tapered interdigitated fingers.
9 . The monolithic isled solar cell of claim 1 , wherein said semiconductor layer is a crystalline silicon layer.
10 . The monolithic isled solar cell of claim 1 , wherein said background doping is an n-type doping.
11 . The monolithic isled solar cell of claim 1 , wherein said monolithic isled solar cell is a back-contact solar cell.
12 . The monolithic isled solar cell of claim 1 , wherein said monolithic isled solar cell is an interdigitated back-contact (IBC) solar cell.
13 . The monolithic isled solar cell of claim 1 , wherein said plurality of monolithic isled semiconductor regions on said insulating support backplane comprises an N×N=N 2 array of isles with N being an integer equal to or greater than 2.
14 . The monolithic isled solar cell of claim 1 , wherein said plurality of monolithic isled semiconductor regions on said insulating support backplane comprises an N×M array of isles with N and M being integers and the product N×M being an integer equal to or greater than 2.
15 . The monolithic isled solar cell of claim 1 , wherein said plurality of monolithic isled semiconductor regions on said insulating support backplane comprises an array of substantially polygonal-shaped isles.
16 . The monolithic isled solar cell of claim 1 , wherein said monolithic isled solar cell produces a voltage scaled up by a factor S and a current scaled down by the same factor S, wherein S is greater than or equal to two.
17 . The monolithic isled solar cell of claim 1 , wherein said patterned first metal layer comprises a plurality of islands of interdigitated pattern of base and emitter fingers without solar cell busbars.
18 . The monolithic isled solar cell of claim 1 , wherein said patterned second metal layer comprises an interdigitated pattern of base and emitter fingers with solar cell busbars.
19 . The monolithic isled solar cell of claim 1 , wherein said semiconductor layer has a thickness in the range of about 1 micron up to about 200 microns.
20 . The monolithic isled solar cell of claim 1 , wherein said insulating support backplane has a thickness in the range of about 50 micron up to about 250 microns.
21 . The monolithic isled solar cell of claim 1 , wherein said insulating support backplane support sheet is a flexible material with relatively close Coefficient of Thermal Expansion (CTE) match to that of said semiconductor layer.
22 . The monolithic isled solar cell of claim 1 , wherein said monolithic isled solar cell is flexible.
23 . The monolithic isled solar cell of claim 1 , wherein said insulating support backplane is a flexible prepreg sheet.
24 . The monolithic isled solar cell of claim 1 , wherein said insulating support backplane is a flexible aramid fiber and resin prepreg sheet.
25 . The monolithic isled solar cell of claim 1 , wherein said trench isolation pattern is an interconnected pattern of trenches.
26 . The monolithic isled solar cell of claim 1 , wherein said plurality of monolithic isled semiconductor regions comprise a N×M array of isles interconnected in electrical series by a combination of said first metal layer and said second metal layer, resulting in scaling up the voltage and scaling down the current of said solar cell.
27 . The monolithic isled solar cell of claim 1 , wherein said plurality of monolithic isled semiconductor regions comprise a N×M array of isles interconnected in a hybrid electrical parallel-series by a combination of said first metal layer and said second metal layer, resulting in scaling up the voltage and scaling down the current of said solar cell.
28 . The monolithic isled solar cell of claim 1 , wherein said plurality of monolithic isled semiconductor regions comprise a N×M array of isles interconnected in electrical parallel by a combination of said first metal layer and said second metal layer.
29 . The monolithic isled solar cell of claim 1 , further comprising a shade management bypass diode.
30 . The monolithic isled solar cell of claim 1 , further comprising a shade management monolithically-integrated bypass switch.