Local metallization of semiconductor substrates using a laser beam, and the resulting structures, e.g., micro-electronic devices, semiconductor substrates and/or solar cells, are described. For example, a solar cell includes a substrate and a plurality of semiconductor regions disposed in or above the substrate. A plurality of conductive contact structures is electrically connected to the plurality of semiconductor regions. Each conductive contact structure includes a locally deposited metal portion disposed in contact with a corresponding a semiconductor region.

The embodiments of the present disclosure describe a stressed Ge PD and fabrications techniques for making the same. In one embodiment, a stressor material is deposited underneath an already formed Ge PD. To do so, wafer bonding can be used to bond the wafer containing the Ge PD to a second, handler wafer. Doing so provides support to remove the substrate of the wafer so that a stressor material (e.g., silicon nitride, diamond-like carbon, or silicon-germanium) can be disposed underneath the Ge PD. The stress material induces a stress or strain in the crystal lattice of the Ge which changes its bandgap and improves its responsivity.

The embodiments of the present disclosure describe a stressed Ge PD and fabrications techniques for making the same. In one embodiment, a stressor material is deposited underneath an already formed Ge PD. To do so, wafer bonding can be used to bond the wafer containing the Ge PD to a second, handler wafer. Doing so provides support to remove the substrate of the wafer so that a stressor material (e.g., silicon nitride, diamond-like carbon, or silicon-germanium) can be disposed underneath the Ge PD. The stress material induces a stress or strain in the crystal lattice of the Ge which changes its bandgap and improves its responsivity.

A method of producing photovoltaic cells with the μ-tandem architecture based on crystalline silicon substrates and quantum dots, ensuring both effective and stable operation of the entire tandem system as well as high absorption in the spectral range from UV to MIR and operation in scattered and incident light conditions at different angles, acting as an anti-reflective layer. A further purpose of the invention is to develop a new structure of a μ-tandem photovoltaic cell based on microcrystalline silicon (Si) layers and a layer of nanometric semiconductor structures with a core-shell architecture such that the resulting structures work as a tandem cell with the characteristics of micro-cells, connected together in its lower part.

A method of producing photovoltaic cells with the μ-tandem architecture based on crystalline silicon substrates and quantum dots, ensuring both effective and stable operation of the entire tandem system as well as high absorption in the spectral range from UV to MIR and operation in scattered and incident light conditions at different angles, acting as an anti-reflective layer. A further purpose of the invention is to develop a new structure of a μ-tandem photovoltaic cell based on microcrystalline silicon (Si) layers and a layer of nanometric semiconductor structures with a core-shell architecture such that the resulting structures work as a tandem cell with the characteristics of micro-cells, connected together in its lower part.

Method and structural embodiments are described which provide an integrated structure using polysilicon material having different optical properties in different regions of the structure.

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.

The present invention is directed to a method as well as to a machine for producing a starting material for a silicon solar cell with passivated contacts.

Discussed is a solar cell including a semiconductor substrate, a first tunneling layer entirely formed over a surface of the semiconductor substrate, a first conductive type area disposed on the surface of the semiconductor substrate, and an electrode including a first electrode connected to the first conductive type area.

A preparation method of a low-cost passivated contact full-back electrode solar cell includes: performing alkali polishing on a Si wafer; performing RCA cleaning and HF cleaning; growing a tunnel SiO.sub.x film layer, an in-situ doped amorphous Si film layer, and a texturing mask layer on the back of the Si wafer; performing annealing activation on the amorphous Si film layer to form a polycrystalline Si film layer; etching the texturing mask layer; performing double-sided texturing on the Si wafer; performing HF cleaning to remove the texturing mask layer; depositing an AlO.sub.x film on the front and back of the Si wafer; depositing a SiN.sub.x passivation film on the front and back of the Si wafer; ablating a part of the AlO.sub.x film and a part of the SiN.sub.x passivation film on the back of the Si wafer; and performing screen-printing and sintering on the back of the Si wafer.