Solar cell element with a carrier (14), a thin film layer structure on a surface of the carrier, the thin film layer structure comprises a transparent first electrode layer (20), active layers (22, 23) in which a portion of the energy of the incident light is absorbed and a second electrode layer (24), the thin film layer structure has a light reflecting rear boundary surface, and the surface of said carrier (14) comprises at least two planar surface regions that close and angle with and form continuation of each other so that between them a recess is formed, and a portion of light reflected from the rear boundary surface of a first surface region will pass through the recess to fall on the second surface region and generates additional charge carriers therein, and the thin film structure on the surface regions constitutes a uniform uninterrupted thin film structure, wherein the extent of absorption of the thin film structure in the visible spectral region of light is at most 90% of the energy of the incident light. A plurality of the solar cell elements forms a solar cell arrangement, in which the carrier (14) is common for all cell elements and a surface of the carrier (14) has a plurality of juxtaposed pyramid-like recesses on which the thin film layers are provided.

Solar cell element with a carrier (14), a thin film layer structure on a surface of the carrier, the thin film layer structure comprises a transparent first electrode layer (20), active layers (22, 23) in which a portion of the energy of the incident light is absorbed and a second electrode layer (24), the thin film layer structure has a light reflecting rear boundary surface, and the surface of said carrier (14) comprises at least two planar surface regions that close and angle with and form continuation of each other so that between them a recess is formed, and a portion of light reflected from the rear boundary surface of a first surface region will pass through the recess to fall on the second surface region and generates additional charge carriers therein, and the thin film structure on the surface regions constitutes a uniform uninterrupted thin film structure, wherein the extent of absorption of the thin film structure in the visible spectral region of light is at most 90% of the energy of the incident light. A plurality of the solar cell elements forms a solar cell arrangement, in which the carrier (14) is common for all cell elements and a surface of the carrier (14) has a plurality of juxtaposed pyramid-like recesses on which the thin film layers are provided.

Disclosed are embodiments of a thin-film photovoltaic technology including a single-junction crystalline silicon solar cell with a photonic-plasmonic back-reflector structure for lightweight, flexible energy conversion applications. The back-reflector enables high absorption for long-wavelength and near-infrared photons via diffraction and light-concentration, implemented by periodic texturing of the bottom-contact layer by nanoimprint lithography. The thin-film crystalline silicon solar cell is implemented in a heterojunction design with amorphous silicon, where plasma enhanced chemical vapor deposition (PECVD) is used for all device layers, including a low-temperature crystalline silicon deposition step. Excimer laser crystallization is used to integrate crystalline and amorphous silicon within a monolithic process, where a thin layer of amorphous silicon is converted to a crystalline silicon seed layer prior to deposition of a crystalline silicon absorber layer via PECVD. The crystalline nature of the absorber layer and the back-reflector enable efficiencies higher than what is achievable in other thin-film silicon devices.

A photodetector comprising a contact layer; an absorbing region positioned such that light admitted passes into the absorbing region; a diffractive region comprising at least one diffractive element operating to diffract light into the absorbing region; the configuration of the photodetector being determined by computer simulation to determine an optimal diffractive region and absorbing region configuration for optimal quantum efficiency for at least one predetermined wavelength range, the diffractive region operating to diffract light entering through the contact layer such that phases of diffracted waves from locations within the photodetector including waves reflected by sidewalls and waves reflected by the diffractive elements form a constructive interference pattern inside the absorbing region. A method of designing a photodetector comprises using a computer simulation to determine an optimal configuration for at least one wavelength range occurring when waves reflected by the diffractive element form a constructive interference pattern inside the absorbing region.

An engineered substrate comprising: a seed layer made of a first semiconductor material for growth of a solar cell; a first bonding layer on the seed layer; a support substrate made of a second semiconductor material; a second bonding layer on a first side of the support substrate; a bonding interface between the first and second bonding layers; the first and second bonding layers each made of metallic material; wherein doping concentration and thickness of the engineered substrate, in particular, of the seed layer, the support substrate, and both the first and second bonding layers, are selected such that the absorption of the seed layer is less than 20%, preferably less than 10%, as well as total area-normalized series resistance of the engineered substrate is less than 10 mOhm.Math.cm.sup.2, preferably less than 5 mOhm.Math.cm.sup.2.

A method for assembling a solar module structure comprises patterning a frontside and a backside of a double-sided printed circuit board coated with metallic foils according to desired frontside and backside interconnect layouts; applying a first coating layer to the rear side of a plurality of three-dimensional thin-film solar cells, each three-dimensional thin-film solar cell comprising: a three-dimensional thin-film solar cell substrate comprising emitter junction regions and doped base regions; emitter metallization and base metallization regions; the three-dimensional thin-film solar cell substrate comprising a plurality of single-aperture unit cells; placing the three-dimensional thin-film solar cells on the frontside of the double-sided printed circuit board; preparing a solar module assembly, comprising: a glass layer; a top encapsulant layer; the plurality of three-dimensional thin-film solar cells on the frontside of the double-sided printed circuit board; a rear encapsulant layer; a protective back plate; and sealing and packaging the solar module assembly.

A method for assembling a solar module structure comprises patterning a frontside and a backside of a double-sided printed circuit board coated with metallic foils according to desired frontside and backside interconnect layouts; applying a first coating layer to the rear side of a plurality of three-dimensional thin-film solar cells, each three-dimensional thin-film solar cell comprising: a three-dimensional thin-film solar cell substrate comprising emitter junction regions and doped base regions; emitter metallization and base metallization regions; the three-dimensional thin-film solar cell substrate comprising a plurality of single-aperture unit cells; placing the three-dimensional thin-film solar cells on the frontside of the double-sided printed circuit board; preparing a solar module assembly, comprising: a glass layer; a top encapsulant layer; the plurality of three-dimensional thin-film solar cells on the frontside of the double-sided printed circuit board; a rear encapsulant layer; a protective back plate; and sealing and packaging the solar module assembly.

A bifacial solar cell module includes solar cells that are protected by front side packaging components and backside packaging components. The front side packaging components include a transparent top cover on a front portion of the solar cell module. The backside packaging components have a transparent portion that allows light coming from a back portion of the solar cell module to reach the solar cells, and a reflective portion that reflects light coming from the front portion of the solar cell module. The transparent and reflective portions may be integrated with a backsheet, e.g., by printing colored pigments on the backsheet. The reflective portion may also be on a reflective component that is separate from the backsheet. In that case, the reflective component may be placed over a clear backsheet before or after packaging.

A bifacial solar cell module includes solar cells that are protected by front side packaging components and backside packaging components. The front side packaging components include a transparent top cover on a front portion of the solar cell module. The backside packaging components have a transparent portion that allows light coming from a back portion of the solar cell module to reach the solar cells, and a reflective portion that reflects light coming from the front portion of the solar cell module. The transparent and reflective portions may be integrated with a backsheet, e.g., by printing colored pigments on the backsheet. The reflective portion may also be on a reflective component that is separate from the backsheet. In that case, the reflective component may be placed over a clear backsheet before or after packaging.

A photonic bandgap structure having multiple stacked layers has a thickness from the top of its top layer to the bottom of its bottom layer of less than one micron. Metal conducting layers having negative real dielectric constants are positioned between semiconductor layers having positive dielectric constants. The layers are arranged and stacked, and the thicknesses and materials for the semiconductor layers and conductive layers are selected to realize desired absorption, transmission, and reflection characteristics.