Disclosed herein are a solar cell and a method of manufacturing the same. The solar cell module includes a semiconductor substrate, a first passivation film located on a front surface of the semiconductor substrate, a second passivation film located on a rear surface of the semiconductor substrate, a front electric field region located on the first passivation film on the front surface of the semiconductor substrate and being of a same conductivity-type as that of the semiconductor substrate, an emitter region located on the second passivation film on the rear surface of the semiconductor substrate and being of a conductivity-type opposite that of the semiconductor substrate, first electrodes conductively connected to the front electric field region, and second electrode conductively connected to the emitter region.

A solar cell module includes: two solar cells, each including: a first main face and a second main face; a first electrode on the first main face, comprising a bus-bar electrode having at least one of an opening portion, notch portion, and gap portion; and a second electrode on the first or second main face having a polarity opposite to that of the first electrode; a wiring member that electrically connects the first electrode of one solar cell to the second electrode of another solar cell; and an electrically conductive connection layer that contacts the wiring member and the first main face.

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.

Solar cell including: a semiconductor substrate of a first conductivity type having a region of the first conductivity type and region of a second conductivity type on the back side; a first finger electrode composed of a first contact portion and first current collector, a second finger electrode composed of a second contact portion and second current collector, a first bus bar electrode, a second bus bar electrode on the backside; an insulator film disposed at least in the area just under the first bus bar electrode and second bus bar electrode; wherein the electrical contact between the first current collector and first bus bar electrode as well as electrical contact between the second current collector and the second bus bar electrode are made on the insulator film; and first contact portion and the second contact portion are in a continuous line shape at least just under the insulator film.

An energy conversion device comprises at least two thin film photovoltaic cells fabricated separately and joined by wafer bonding. The cells are arranged in a hierarchical stack of decreasing order of their energy bandgap from top to bottom. Each of the thin film cells has a thickness in the range from about 0.5 m to about 10 m. The photovoltaic cell stack is mounted upon a thick substrate composed of a material selected from silicon, glass, quartz, silica, alumina, ceramic, metal, graphite, and plastic. Each of the interfaces between the cells comprises a structure selected from a tunnel junction, a heterojunction, a transparent conducting oxide, and an alloying metal grid; and the top surface and/or the lower surface of the energy conversion device may contain light-trapping means.

A solar cell of the present invention includes a collecting electrode on one main surface of a photoelectric conversion section. The collecting electrode includes first and second electroconductive layers in this order from the photoelectric conversion section side, and an insulating layer between the first and second electroconductive layers, the insulating layer having an opening section formed therein. The first electroconductive layer is covered with the insulating layer, contains a low-melting-point material, and is conductively connected with a part of the second electroconductive layer via the opening section. The surface roughness of the second electroconductive layer is preferably 1.0 m to 10.0 m. The second electroconductive layer is preferably formed by a plating method. In order to conductively connect the first and second electroconductive layers, annealing of the first electroconductive layer by heating is preferably performed prior to forming the second electroconductive layer.

An energy conversion device comprises at least two thin film photovoltaic cells fabricated separately and joined by wafer bonding. The cells are arranged in a hierarchical stack of decreasing order of their energy bandgap from top to bottom. Each of the thin film cells has a thickness in the range from about 0.5 m to about 10 m. The photovoltaic cell stack is mounted upon a thick substrate composed of a material selected from silicon, glass, quartz, silica, alumina, ceramic, metal, graphite, and plastic. Each of the interfaces between the cells comprises a structure selected from a tunnel junction, a heterojunction, a transparent conducting oxide, and an alloying metal grid; and the top surface and/or the lower surface of the energy conversion device may contain light-trapping means.

Methods for fabricating busbar and finger metallization over TCO are disclosed. Rather than using expensive and relatively resistive silver paste, a high conductivity and relatively low cost copper is used. Methods for enabling the use of copper as busbar and fingers over a TCO are disclosed, providing good adhesion while preventing migration of the copper into the TCO. Also, provisions are made for easy soldering contacts to the copper busbars.

Methods of fabricating solar cell emitter regions using self-aligned implant and cap, and the resulting solar cells, are described. In an example, a method of fabricating an emitter region of a solar cell involves forming a silicon layer above a substrate. The method also involves implanting, through a stencil mask, dopant impurity atoms in the silicon layer to form implanted regions of the silicon layer with adjacent non-implanted regions. The method also involves forming, through the stencil mask, a capping layer on and substantially in alignment with the implanted regions of the silicon layer. The method also involves removing the non-implanted regions of the silicon layer, wherein the capping layer protects the implanted regions of the silicon layer during the removing. The method also involves annealing the implanted regions of the silicon layer to form doped polycrystalline silicon emitter regions.

A method for fabricating a solar cell is disclosed. The method can include forming a dielectric region on a surface of a solar cell structure and forming a first metal layer on the dielectric region. The method can also include forming a second metal layer on the first metal layer and locally heating a particular region of the second metal layer, where heating includes forming a metal bond between the first and second metal layer and forming a contact between the first metal layer and the solar cell structure. The method can include forming an adhesive layer on the first metal layer and forming a second metal layer on the adhesive layer, where the adhesive layer mechanically couples the second metal layer to the first metal layer and allows for an electrical connection between the second metal layer to the first metal layer.