After forming an absorber layer containing cracks over a back contact layer, a passivation layer is formed over a top surface of the absorber layer and interior surfaces of the cracks. The passivation layer is deposited in a manner such that that the cracks in the absorber layer are fully passivated by the passivation layer. An emitter layer is then formed over the passivation layer to pinch off upper portions of the cracks, leaving voids in lower portions of the cracks.

Methods of fabricating solar cell emitter regions with differentiated P-type and N-type regions architectures, and resulting solar cells, are described. In an example, a back contact solar cell includes a substrate having a light-receiving surface and a back surface. A first polycrystalline silicon emitter region of a first conductivity type is disposed on a first thin dielectric layer disposed on the back surface of the substrate. A second polycrystalline silicon emitter region of a second, different, conductivity type is disposed on a second thin dielectric layer disposed on the back surface of the substrate. A third thin dielectric layer is disposed laterally directly between the first and second polycrystalline silicon emitter regions. A first conductive contact structure is disposed on the first polycrystalline silicon emitter region. A second conductive contact structure is disposed on the second polycrystalline silicon emitter region.

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.

Methods of fabricating solar cells using a metal-containing thermal and diffusion barrier layer in foil-based metallization approaches, and the resulting solar cells, are described. For example, a method of fabricating a solar cell includes forming a plurality of semiconductor regions in or above a substrate. The method also includes forming a metal-containing thermal and diffusion barrier layer above the plurality of semiconductor regions. The method also includes forming a metal seed layer on the metal-containing thermal and diffusion barrier layer. The method also includes forming a metal conductor layer on the metal seed layer. The method also includes laser welding the metal conductor layer to the metal seed layer. The metal-containing thermal and diffusion barrier layer protects the plurality of semiconductor regions during the laser welding.

A material for photo-electric conversion has a multi-layered diamond-like film including an upper layer possessing electrical conductivity of one type and a lower layer possessing electrical conductivity of another different type, and a photo-electric converter is provided with this material and converts light into electric current.

The invention relates to a method for producing a photovoltaic solar cell having at least one hetero-junction, including the following steps: A) providing a semiconductor substrate having base doping; B) producing a hetero-junction on at least one side of the semiconductor substrate, which hetero-junction has a doped hetero-junction layer and a dielectric tunnel layer arranged indirectly or directly between the hetero-junction layer and the semiconductor substrate; C) heating at least the hetero-junction layer in order to improve the electrical quality of the heterojunction. The invention is characterized in that, in a step D after step C, hydrogen is diffused into the hetero-junction layer and/or to the interface between the tunnel layer and the semiconductor substrate.

A Tunnel Oxide Passivated Contact (TOPCon) solar cell, and a method therefor are provided. The TOPCon solar cell includes: a silicon substrate; a tunneling layer formed on a surface of the silicon substrate; a polycrystalline silicon layer formed on a surface of the tunneling layer; a polycrystalline germanium layer formed on a surface of the polycrystalline silicon layer; a lower passivation layer formed on a surface of the polycrystalline germanium layer; and a lower electrode formed on the lower passivation layer and electrically connected to the polycrystalline germanium layer.

Provided are an interdigitated back contact solar cell (10,a,b,c), comprising a monocrystalline, n-doped wafer (101), a first contact area (40) which is formed by a first stack on the surface of said monocrystalline wafer (101), said first stack comprising a thin silicon oxide layer (201) and a highly n-doped polycrystalline silicon layer (301), and a second contact area (20) which is formed by a second stack on the same surface of said monocrystalline wafer (101) as said first stack, said second stack comprising a thin silicon oxide layer (202) and a highly p-doped polycrystalline silicon layer (701), wherein a p-doped monocrystalline silicon region (801) is located in a gap (30) between said first contact area (40) and said second contact area (20) and a method for producing such an interdigitated back contact solar cell (10,a,b,c).

After forming an absorber layer containing cracks over a back contact layer, a passivation layer is formed over a top surface of the absorber layer and interior surfaces of the cracks. The passivation layer is deposited in a manner such that that the cracks in the absorber layer are fully passivated by the passivation layer. An emitter layer is then formed over the passivation layer to pinch off upper portions of the cracks, leaving voids in lower portions of the cracks.

Approaches for foil-based metallization of solar cells and the resulting solar cells are described. For example, a method of fabricating a solar cell involves locating a metal foil above a plurality of alternating N-type and P-type semiconductor regions disposed in or above a substrate. The method also involves laser welding the metal foil to the alternating N-type and P-type semiconductor regions. The method also involves patterning the metal foil by laser ablating through at least a portion of the metal foil at regions in alignment with locations between the alternating N-type and P-type semiconductor regions. The laser welding and the patterning are performed at the same time.