Photovoltaic sub-cell interconnects
Photovoltaic sub-cell interconnect systems and methods are provided. In one embodiment, a photovoltaic device comprises a thin film stack of layers deposited upon a substrate, wherein the thin film stack layers are subdivided into a plurality of sub-cells interconnected in series by a plurality of electrical interconnection structures; and wherein the plurality of electrical interconnection structures each comprise no more than two scribes that penetrate into the thin film stack layers.
1. A method comprising:
opening, in a device comprising thin film stack layers deposited on a substrate, a first scribe through a top contact layer, an absorber layer, and a bottom contact layer of the thin film stack layers, wherein the first scribe divides the thin film stack layers into a first sub-cell and a second sub-cell, and wherein the first scribe exposes a side of the bottom contact layer of the first sub-cell and a side of the bottom contact layer of the second sub-cell;
printing, subsequent to opening the first scribe, one or more layers of an insulator material across a bottom of the first scribe, from the first sub-cell to the second sub-cell, such that the insulator material covers the side of the bottom contact layer of the first sub-cell and the side of the bottom contact layer of the second sub-cell;
opening, subsequent to printing the insulator material, a second scribe in the second sub-cell, adjacent to the first scribe, from the top contact layer and sufficiently through the thin film stack layers to expose at least a portion of the bottom contact layer of the second sub-cell; and
depositing, subsequent to opening the second scribe, an electrically conducting material into the first and second scribes such that the electrically conducting material electrically couples the top contact layer of the first sub-cell to the bottom contact layer of the second sub-cell, wherein the insulator material electrically insulates the electrically conducting material from the bottom contact layer of the first sub-cell.
2. The method of claim 1 , wherein the substrate is non-conductive.
3. The method of claim 1 , wherein the thin film stack layers further comprise a window layer between the absorber layer and the bottom contact layer.
4. The method of claim 1 , wherein the absorber layer comprises a P-N photovoltaic junction comprising at least one of CdTe, InP, copper indium selenide (CIS), copper indium gallium diselenide (CIGS), crystalline-Si, amorphous-Si, or an organic semiconductor material.
5. The method of claim 1 , wherein each of the first scribe and the second scribe is opened using at least one of a mechanical scribing tool or a laser scribing tool.
6. The method of claim 1 , wherein the substrate is electrically conductive and wherein the thin film stack layers further comprise a dielectric material layer positioned between the substrate and the bottom contact layer.