Abstract: Methods of fabricating a solar cell, and system for electrically coupling solar cells, are described. In an example, the methods for fabricating a solar cell can include placing conductive wires in a wire guide, where conductive wires are placed over a first semiconductor substrate having first doped regions and second doped regions. The method can include aligning the conductive wires over the first and second doped regions, where the wire guide aligns the conductive wires substantially parallel to the first and second doped regions. The method can include bonding the conductive wires to the first and second doped regions. The bonding can include applying a mechanical force to the semiconductor substrate via a roller or bonding head of the wire guide, where the wire guide inhibits lateral movement of the conductive wires during the bonding.

Abstract: Approaches for fabricating wire-based metallization for solar cells, and the resulting solar cells, are described. In an example, a solar cell includes a substrate having a back surface and an opposing light-receiving surface. A plurality of alternating N-type and P-type semiconductor regions is disposed in or above the back surface of the substrate. A conductive contact structure is disposed on the plurality of alternating N-type and P-type semiconductor regions. The conductive contact structure includes a plurality of metal wires. Each metal wire of the plurality of metal wires is parallel along a first direction to form a one-dimensional layout of a metallization layer for the solar cell.

Abstract: A solar cell can include a substrate and a semiconductor region disposed in or above the substrate. The solar cell can also include a conductive contact disposed on the semiconductor region with the conductive contact including a conductive foil bonded to the semiconductor region.

Abstract: A solar cell can include a conductive foil having a first portion with a first yield strength coupled to a semiconductor region of the solar cell. The solar cell can be interconnected with another solar cell via an interconnect structure that includes a second portion of the conductive foil, with the interconnect structure having a second yield strength greater than the first yield strength.

Abstract: A multi-axis flattening tool and method are described. In an example, the multi-axis flattening tool includes a support structure to constrain a bowed wafer along a support perimeter, and a pair of flattening structures independently movable relative to the support structure. For example, a first flattening structure may grip the wafer within the support perimeter and move axially relative to the support structure to bend the wafer about a first plane, and a second flattening structure may grip the wafer within the support perimeter and move axially relative to the support structure to bend the wafer about a second plane orthogonal to the first plane. The multi-axis bending of the wafer may flatten the wafer.

Abstract: Die-cutting approaches for foil-based metallization of solar cells, and the resulting solar cells are disclosed herein. Die-cutting approaches for foil-based metallization of solar cells include forming a plurality of semiconductor regions in or above a substrate and forming a patterned damage buffer in alignment with locations between the plurality of semiconductor regions. Additionally, a metal layer comprising a metal seed layer and/or metal foil is formed over the patterned damage buffer. The metal layer is cut by a cutting die at locations between the plurality of semiconductor regions by applying a mechanical force to the cutting die.

Abstract: Disclosed herein are approaches to fabricating solar cells, solar cell strings and solar modules using roll-to-roll foil-based metallization approaches. Methods disclosed herein can comprise the steps of providing at least one solar cell wafer on a first roll unit and conveying a metal foil to the first roll unit. The metal foil can be coupled to the solar cell wafer on the first roll unit to produce a unified pairing of the metal foil and the solar cell wafer. We disclose solar energy collection devices and manufacturing methods thereof enabling reduction of manufacturing costs due to simplification of the manufacturing process by a high throughput foil metallization process.

Abstract: A solar cell can include a substrate and a semiconductor region disposed in or above the substrate. The solar cell can also include a conductive contact disposed on the semiconductor region with the conductive contact including a conductive foil bonded to the semiconductor region.

Abstract: Thermocompression bonding approaches for foil-based metallization of non-metal surfaces of solar cells, and the resulting solar cells, are described. For example, a solar cell includes a substrate and a plurality of alternating N-type and P-type semiconductor regions disposed in or above the substrate. A plurality of conductive contact structures is electrically connected to the plurality of alternating N-type and P-type semiconductor regions. Each conductive contact structure includes a metal foil portion disposed in direct contact with a corresponding one of the alternating N-type and P-type semiconductor regions.

Abstract: Die-cutting approaches for foil-based metallization of solar cells, and the resulting solar cells are disclosed herein. Die-cutting approaches for foil-based metallization of solar cells include forming a plurality of semiconductor regions in or above a substrate and forming a patterned damage buffer in alignment with locations between the plurality of semiconductor regions. Additionally, a metal layer comprising a metal seed layer and/or metal foil is formed over the patterned damage buffer. The metal layer is cut by a cutting die at locations between the plurality of semiconductor regions by applying a mechanical force to the cutting die.

Abstract: Approaches for the foil-based metallization of solar cells and the resulting solar cells are described. In an example, a solar cell includes a substrate. A plurality of alternating N-type and P-type semiconductor regions is disposed in or above the substrate. A conductive contact structure is disposed above the plurality of alternating N-type and P-type semiconductor regions. The conductive contact structure includes a plurality of metal seed material regions providing a metal seed material region disposed on each of the alternating N-type and P-type semiconductor regions. A metal foil is disposed on the plurality of metal seed material regions, the metal foil having anodized portions isolating metal regions of the metal foil corresponding to the alternating N-type and P-type semiconductor regions.

Abstract: Thermal compression bonding approaches for foil-based metallization of solar cells, and the resulting solar cells, are described. For example, a method of fabricating a solar cell includes placing a metal foil over a metalized surface of a wafer of the solar cell. The method also includes locating the metal foil with the metalized surface of the wafer. The method also includes, subsequent to the locating, applying a force to the metal foil such that a shear force appears between the metal foil and the metallized surface of the wafer to electrically connect a substantial portion of the metal foil with the metalized surface of the wafer.

Abstract: Laser foil trim approaches for foil-based metallization of solar cells, and the resulting solar cells, are described. For example, a method of fabricating a solar cell includes attaching a metal foil sheet to a surface of a wafer to provide a unified pairing of the metal foil sheet and the wafer, wherein the wafer has a perimeter and the metal foil sheet has a portion overhanging the perimeter. The method also includes laser scribing the metal foil sheet along the perimeter of the wafer using a laser beam that overlaps the metal foil sheet outside of the perimeter of the wafer and at the same time overlaps a portion of the unified pairing of the metal foil sheet and the wafer inside the perimeter of the wafer to remove the portion of the metal foil sheet overhanging the perimeter and to provide a metal foil piece coupled to the surface of the wafer.

Abstract: A solar cell can include a substrate and a semiconductor region disposed in or above the substrate. The solar cell can also include a conductive contact disposed on the semiconductor region with the conductive contact including a paste, a first metal, and a first conductive portion that includes a conductive alloy formed from the first metal at an interface of the substrate and the semiconductor region.

Abstract: A solar cell can include a conductive foil having a first portion with a first yield strength coupled to a semiconductor region of the solar cell. The solar cell can be interconnected with another solar cell via an interconnect structure that includes a second portion of the conductive foil, with the interconnect structure having a second yield strength greater than the first yield strength.

Abstract: Laser foil trim approaches for foil-based metallization of solar cells, and the resulting solar cells, are described. For example, a method of fabricating a solar cell includes attaching a metal foil sheet to a surface of a wafer to provide a unified pairing of the metal foil sheet and the wafer, wherein the wafer has a perimeter and the metal foil sheet has a portion overhanging the perimeter. The method also includes laser scribing the metal foil sheet along the perimeter of the wafer using a laser beam that overlaps the metal foil sheet outside of the perimeter of the wafer and at the same time overlaps a portion of the unified pairing of the metal foil sheet and the wafer inside the perimeter of the wafer to remove the portion of the metal foil sheet overhanging the perimeter and to provide a metal foil piece coupled to the surface of the wafer.

Abstract: Indentation approaches for foil-based metallization of solar cells, and the resulting solar cells, are described. For example, a method of fabricating a solar cell includes forming a plurality of alternating N-type and P-type semiconductor regions in or above a substrate. The method also includes locating a metal foil above the alternating N-type and P-type semiconductor regions. The method also includes forming a plurality of indentations through only a portion of the metal foil, the plurality of indentations formed at regions corresponding to locations between the alternating N-type and P-type semiconductor regions. The method also includes, subsequent to forming the plurality of indentations, isolating regions of the remaining metal foil corresponding to the alternating N-type and P-type semiconductor regions.

Abstract: Approaches for the foil-based metallization of solar cells and the resulting solar cells are described. In an example, a solar cell includes a substrate. A plurality of alternating N-type and P-type semiconductor regions is disposed in or above the substrate. A conductive contact structure is disposed above the plurality of alternating N-type and P-type semiconductor regions. The conductive contact structure includes a plurality of metal seed material regions providing a metal seed material region disposed on each of the alternating N-type and P-type semiconductor regions. A metal foil is disposed on the plurality of metal seed material regions, the metal foil having anodized portions isolating metal regions of the metal foil corresponding to the alternating N-type and P-type semiconductor regions.

Abstract: Laser foil trim approaches for foil-based metallization of solar cells, and the resulting solar cells, are described. For example, a method of fabricating a solar cell includes attaching a metal foil sheet to a surface of a wafer to provide a unified pairing of the metal foil sheet and the wafer, wherein the wafer has a perimeter and the metal foil sheet has a portion overhanging the perimeter. The method also includes laser scribing the metal foil sheet along the perimeter of the wafer using a laser beam that overlaps the metal foil sheet outside of the perimeter of the wafer and at the same time overlaps a portion of the unified pairing of the metal foil sheet and the wafer inside the perimeter of the wafer to remove the portion of the metal foil sheet overhanging the perimeter and to provide a metal foil piece coupled to the surface of the wafer.

Abstract: A solar cell can include a substrate and a semiconductor region disposed in or above the substrate. The solar cell can also include a conductive contact disposed on the semiconductor region with the conductive contact including a paste, a first metal, and a first conductive portion that includes a conductive alloy formed from the first metal at an interface of the substrate and the semiconductor region.