Abstract: One embodiment of the present invention provides a solar cell. The solar cell includes a photovoltaic structure and a front-side metal grid situated above the photovoltaic structure. The front-side metal grid also includes one or more electroplated metal layers. The front-side metal grid includes one or more finger lines, and each end of a respective finger line is coupled to a corresponding end of an adjacent finger line via an additional metal line, thus ensuring that the respective finger line has no open end.

Abstract: One embodiment of the present invention provides a solar cell. The solar cell includes a base layer comprising crystalline Si (c-Si), a hole collector situated on a first side of the base layer, and an electron collector situated on a second side of the base layer, which is opposite the first side. The hole collector includes a quantum-tunneling-barrier (QTB) layer situated adjacent to the base layer and a transparent conducting oxide (TCO) layer situated adjacent to the QTB layer. The TCO layer has a work function of at least 5.0 eV.

Abstract: One embodiment of the present invention provides a tunneling junction based solar cell. The solar cell includes a base layer; a quantum-tunneling-barrier (QTB) layer situated adjacent to the base layer; an emitter; a surface field layer; a front-side electrode; and a back-side electrode.

Abstract: A magnetron sputter reactor for sputtering deposition materials such as tantalum, tantalum nitride and copper, for example, and its method of use, in which self-ionized plasma (SIP) sputtering and inductively coupled plasma (ICP) sputtering are promoted, either together or alternately, in the same or different chambers. Also, bottom coverage may be thinned or eliminated by ICP resputtering in one chamber and SIP in another. SIP is promoted by a small magnetron having poles of unequal magnetic strength and a high power applied to the target during sputtering. ICP is provided by one or more RF coils which inductively couple RF energy into a plasma. The combined SIP-ICP layers can act as a liner or barrier or seed or nucleation layer for hole. In addition, an RF coil may be sputtered to provide protective material during ICP resputtering. In another chamber an array of auxiliary magnets positioned along sidewalls of a magnetron sputter reactor on a side towards the wafer from the target.

Abstract: One embodiment of the present invention provides a method for fabricating a solar cell. The method includes: melting a metallurgical-grade (MG) Si feedstock, lowering a single-crystalline Si seed to touch the surface of the molten MG-Si, slowly pulling out a single-crystal Si ingot of the molten MG-Si, processing the Si ingot into single crystal Si wafers to form MG-Si substrates for subsequent epitaxial growth, leaching out residual metal impurities in the MG-Si substrate, epitaxially growing a layer of single-crystal Si thin film doped with boron on the MG-Si substrate, doping phosphor to the single-crystal Si thin film to form an emitter layer, depositing an anti-reflection layer on top of the single-crystal Si thin film, and forming the front and the back electrical contacts.

Abstract: One embodiment of the present invention provides a tunneling junction solar cell. The solar cell includes a base layer, an emitter layer situated adjacent to the shallow counter doping layer, a surface field layer situated adjacent to a side of the base layer opposite to the shallow counter doping layer, a front-side electrode, and a back-side electrode. The base layer includes a shallow counter doping layer having a conduction doping type that is opposite to a remainder of the base layer. The emitter layer has a bandgap that is wider than that of the base layer.

Abstract: One embodiment of the present invention provides a back junction solar cell. The solar cell includes a base layer, a quantum-tunneling-barrier (QTB) layer situated below the base layer facing away from incident light, an emitter layer situated below the QTB layer, a front surface field (FSF) layer situated above the base layer, a front-side electrode situated above the FSF layer, and a back-side electrode situated below the emitter layer.

Abstract: One embodiment of the present invention provides a photovoltaic module. The photovoltaic module includes an optical concentrator and a tunneling-junction solar cell. The tunneling junction solar cell includes a base layer, a quantum-tunneling-barrier (QTB) layer situated above the base layer, an emitter layer, a front-side electrode, and a back-side electrode.

Abstract: One embodiment of the present invention provides a solar cell. The solar cell includes a metallurgical-grade Si (MG-Si) substrate, a first layer of heavily doped crystalline-Si situated above the MG-Si substrate, a layer of lightly doped crystalline-Si situated above the first heavily doped crystalline-Si layer, a backside ohmic-contact layer situated on the backside of the MG-Si substrate, a second layer of heavily doped crystalline-Si situated above the lightly doped crystalline-Si layer, a first layer of dielectric situated above the second heavily doped crystalline-Si layer, a second layer of dielectric situated above the first dielectric layer, and front electrodes situated above the second dielectric layer.

Abstract: One embodiment of the present invention provides a heterojunction solar cell. The solar cell includes a metallurgical-grade Si (MG-Si) substrate, a layer of heavily doped crystalline-Si situated above the MG-Si substrate, a layer of lightly doped crystalline-Si situated above the heavily doped crystalline-Si layer, a backside ohmic-contact layer situated on the backside of the MG-Si substrate, a passivation layer situated above the heavily doped crystalline-Si layer, a layer of heavily doped amorphous Si (a-Si) situated above the passivation layer, a layer of transparent-conducting-oxide (TCO) situated above the heavily doped a-Si layer, and a front ohmic-contact electrode situated above the TCO layer.

Abstract: One embodiment of the present invention provides a solar cell panel that includes a front-side cover, a back-side cover, a number of solar cells situated between the front-side cover and the back-side cover, and a number of maximum power point tracking (MPPT) devices situated between the front-side cover and the back-side cover.

Abstract: One embodiment of the present invention provides a method for fabricating solar cells. During operation, an anti-reflection layer is deposited on top of a semiconductor structure to form a photovoltaic structure, and a front-side electrode grid comprising a metal stack is formed on top of the photovoltaic structure. The metal stack comprises a metal-adhesive layer comprising Ti or Ta, and a conducting layer comprising Cu or Ag situated above the metal-adhesive layer.

Abstract: One embodiment of the present invention provides a solar cell. The solar cell includes a Si base layer, a passivation layer situated above the Si base layer, a layer of heavily doped amorphous Si (a-Si) situated above the passivation layer, a first transparent-conducting-oxide (TCO) layer situated above the heavily doped a-Si layer, a back-side electrode situated below the Si base layer, and a front-side electrode situated above the first TCO layer. The first TCO layer comprises at least one of: GaInO, GaInSnO, ZnInO, and ZnInSnO.

Abstract: One embodiment of the present invention provides a solar cell. The solar cell includes a photovoltaic structure, a transparent-conductive-oxide (TCO) layer situated above the photovoltaic structure, and a front-side metal grid situated above the TCO layer. The TCO layer is in contact with the front surface of the photovoltaic structure. The metal grid includes at least one of: Cu and Ni.

Abstract: One embodiment of the present invention provides a solar cell with shade-free front electrode. The solar cell includes a photovoltaic body, a front-side ohmic contact layer situated above the photovoltaic body, a back-side ohmic contact layer situated below the photovoltaic body, a front-side electrode situated above the front-side ohmic contact layer, and a back-side electrode situated below the back-side ohmic contact layer. The front-side electrode includes a plurality of parallel metal grid lines, and the surface of at least one metal grid line is curved, thereby allowing incident light hitting the curved surface to be reflected downward and absorbed by the solar cell surface adjacent to the metal grid line.

Abstract: One embodiment of the present invention provides a tunneling junction based solar cell. The solar cell includes a base layer; a quantum-tunneling-barrier (QTB) layer situated adjacent to the base layer; an emitter; a surface field layer; a front-side electrode; and a back-side electrode.

Abstract: One embodiment of the present invention provides a solar cell. The solar cell includes a substrate, a first heavily doped crystalline-Si (c-Si) layer situated above the substrate, a lightly doped c-Si layer situated above the first heavily doped crystalline-Si layer, a second heavily doped c-Si layer situated above the lightly doped c-Si layer, a front side electrode grid situated above the second heavily doped c-Si layer, and a backside electrode grid situated on the backside of the substrate.

Abstract: One embodiment of the present invention provides a double-sided heterojunction solar cell module. The solar cell includes a frontside glass cover, a backside glass cover situated below the frontside glass cover, and a number of solar cells situated between the frontside glass cover and the backside glass cover. Each solar cell includes a semiconductor multilayer structure situated below the frontside glass cover, including: a frontside electrode grid, a first layer of heavily doped amorphous Si (a-Si) situated below the frontside electrode, a layer of lightly doped crystalline-Si (c-Si) situated below the first layer of heavily doped a-Si, and a layer of heavily doped c-Si situated below the lightly doped c-Si layer. The solar cell also includes a second layer of heavily doped a-Si situated below the multilayer structure; and a backside electrode situated below the second layer of heavily doped a-Si.

Abstract: One embodiment of the present invention provides a double-sided heterojunction solar cell module. The solar cell includes a frontside glass cover, a backside cover situated below the frontside glass cover, and a number of solar cells situated between the frontside glass cover and the backside glass cover. Each solar cell includes a semiconductor multilayer structure situated below the frontside glass cover, including: a frontside electrode grid, a first layer of heavily doped amorphous Si (a-Si) situated below the frontside electrode, a layer of lightly doped crystalline-Si (c-Si) situated below the first layer of heavily doped a-Si, and a layer of heavily doped c-Si situated below the lightly doped c-Si layer. The solar cell also includes a second layer of heavily doped a-Si situated below the multilayer structure; and a backside electrode situated below the second layer of heavily doped a-Si.

Abstract: One embodiment of the present invention provides a solar cell. The solar cell includes a metallurgical-grade Si (MG-Si) substrate, a first layer of heavily doped crystalline-Si situated above the MG-Si substrate, a layer of lightly doped crystalline-Si situated above the first heavily doped crystalline-Si layer, a backside ohmic-contact layer situated on the backside of the MG-Si substrate, a second layer of heavily doped crystalline-Si situated above the lightly doped crystalline-Si layer, a first layer of dielectric situated above the second heavily doped crystalline-Si layer, a second layer of dielectric situated above the first dielectric layer, and front electrodes situated above the second dielectric layer.