Abstract: Methods and apparatus for converting electromagnetic radiation, such as solar energy, into electric energy with increased efficiency when compared to conventional solar cells are provided. A photovoltaic (PV) device generally includes a window layer; an absorber layer disposed below the window layer such that electrons are generated when photons travel through the window layer and are absorbed by the absorber layer; and a plurality of contacts for external connection coupled to the absorber layer, such that all of the contacts for external connection are disposed below the absorber layer and do not block any of the photons from reaching the absorber layer through the window layer. Locating all the contacts on the back side of the PV device avoids solar shadows caused by front side contacts, typically found in conventional solar cells. Therefore, PV devices described herein with back side contacts may allow for increased efficiency when compared to conventional solar cells.

Abstract: An optoelectronic device and a method for fabricating the optoelectronic device are disclosed. The optoelectronic device comprises a p-n structure, a patterned dielectric layer comprising a dielectric material and a metal layer disposed on the dielectric layer. The metal layer makes one or more contact to the p-n structure through the patterned dielectric layer. The dielectric material may be chemically resistant to acids and may provide adhesion to the p-n structure and the metal layer. The method for fabricating an optoelectronic device comprises providing a p-n structure, providing a dielectric layer on the p-n structure and providing a metal layer on the dielectric layer and then lifting the device off the substrate, such that after the lift off the p-n structure is closer than the patterned dielectric layer to a front side of the device; wherein the device comprises the p-n structure, the patterned dielectric layer, and the metal layer.

Abstract: Methods and apparatus are provided for converting electromagnetic radiation, such as solar energy, into electric energy with increased efficiency when compared to conventional solar cells. One embodiment of the present invention provides a photovoltaic (PV) device. The PV device comprises an absorber layer made of a compound semiconductor; and an emitter layer located closer than the absorber layer to a first side of the device. The PV device includes a p-n junction formed between the emitter layer and the absorber layer, the p-n junction causing a voltage to be generated in the device in response to the device being exposed to light at a second side of the device. Such innovations may allow for greater efficiency and flexibility in PV devices when compared to conventional solar cells.

Abstract: Methods and apparatus are provided for converting electromagnetic radiation, such as solar energy, into electric energy with increased efficiency when compared to conventional solar cells. One embodiment of the present invention provides a photovoltaic (PV) device. The PV device comprises an absorber layer made of a compound semiconductor; and an emitter layer located closer than the absorber layer to a first side of the device. The PV device includes a p-n junction formed between the emitter layer and the absorber layer, the p-n junction causing a voltage to be generated in the device in response to the device being exposed to light at a second side of the device. Such innovations may allow for greater efficiency and flexibility in PV devices when compared to conventional solar cells.

Abstract: Methods and apparatus are provided for converting electromagnetic radiation, such as solar energy, into electric energy with increased efficiency when compared to conventional solar cells. One embodiment of the present invention provides a photovoltaic (PV) device. The PV device comprises an absorber layer made of a compound semiconductor; and an emitter layer located closer than the absorber layer to a first side of the device. The PV device includes a p-n junction formed between the emitter layer and the absorber layer, the p-n junction causing a voltage to be generated in the device in response to the device being exposed to light at a second side of the device. Such innovations may allow for greater efficiency and flexibility in PV devices when compared to conventional solar cells.

Abstract: Epitaxial lift off systems and methods are presented. In one embodiment a tape is disposed on the opposite side of the epitaxial material than the substrate is used to hold the epitaxial material during the etching and removal steps of the ELO process. In various embodiments, the apparatus for removing the ELO film from the substrates without damaging the ELO film may include an etchant reservoir, substrate handling and tape handling mechanisms, including mechanisms to manipulate (e.g., cause tension, peel, widen the etch gap, etc.) the lift off component during the lift off process.

Abstract: An optoelectronic device and a method for fabricating the optoelectronic device are disclosed. The optoelectronic device comprises a p-n structure, a patterned dielectric layer comprising a dielectric material and a metal layer disposed on the dielectric layer. The metal layer makes one or more contact to the p-n structure through the patterned dielectric layer. The dielectric material may be chemically resistant to acids and may provide adhesion to the p-n structure and the metal layer. The method for fabricating an optoelectronic device comprises providing a p-n structure, providing a dielectric layer on the p-n structure and providing a metal layer on the dielectric layer and then lifting the device off the substrate, such that after the lift off the p-n structure is closer than the patterned dielectric layer to a front side of the device; wherein the device comprises the p-n structure, the patterned dielectric layer, and the metal layer.

Abstract: Epitaxial lift off systems and methods are presented. In one embodiment a tape is disposed on the opposite side of the epitaxial material than the substrate is used to hold the epitaxial material during the etching and removal steps of the ELO process. In various embodiments, the apparatus for removing the ELO film from the substrates without damaging the ELO film may include an etchant reservoir, substrate handling and tape handling mechanisms, including mechanisms to manipulate (e.g., cause tension, peel, widen the etch gap, etc.) the lift off component during the lift off process.

Abstract: An optoelectronic device and a method for fabricating the optoelectronic device are disclosed. The optoelectronic device comprises a p-n structure, a patterned dielectric layer comprising a dielectric material and a metal layer disposed on the dielectric layer. The metal layer makes one or more contact to the p-n structure through the patterned dielectric layer. The dielectric material may be chemically resistant to acids and may provide adhesion to the p-n structure and the metal layer. The method for fabricating an optoelectronic device comprises providing a p-n structure, providing a dielectric layer on the p-n structure and providing a metal layer on the dielectric layer and then lifting the device off the substrate, such that after the lift off the p-n structure is closer than the patterned dielectric layer to a front side of the device; wherein the device comprises the p-n structure, the patterned dielectric layer, and the metal layer.

Abstract: Methods and apparatus for converting electromagnetic radiation, such as solar energy, into electric energy with increased efficiency when compared to conventional solar cells are provided. A photovoltaic (PV) device generally includes a window layer; an absorber layer disposed below the window layer such that electrons are generated when photons travel through the window layer and are absorbed by the absorber layer; and a plurality of contacts for external connection coupled to the absorber layer, such that all of the contacts for external connection are disposed below the absorber layer and do not block any of the photons from reaching the absorber layer through the window layer. Locating all the contacts on the back side of the PV device avoids solar shadows caused by front side contacts, typically found in conventional solar cells. Therefore, PV devices described herein with back side contacts may allow for increased efficiency when compared to conventional solar cells.

Abstract: Methods and apparatus for converting electromagnetic radiation, such as solar energy, into electric energy with increased efficiency when compared to conventional solar cells are provided. A photovoltaic (PV) device generally includes a window layer; an absorber layer disposed below the window layer such that electrons are generated when photons travel through the window layer and are absorbed by the absorber layer; and a plurality of contacts for external connection coupled to the absorber layer, such that all of the contacts for external connection are disposed below the absorber layer and do not block any of the photons from reaching the absorber layer through the window layer. Locating all the contacts on the back side of the PV device avoids solar shadows caused by front side contacts, typically found in conventional solar cells. Therefore, PV devices described herein with back side contacts may allow for increased efficiency when compared to conventional solar cells.

Abstract: Methods and apparatus are provided for converting electromagnetic radiation, such as solar energy, into electric energy with increased efficiency when compared to conventional solar cells. A photovoltaic (PV) unit may have all electrical contacts positioned on the back side of the PV device to avoid shadowing and increase absorption of the photons impinging on the front side of the PV unit. Several PV units may be combined into PV banks, and an array of PV banks may be connected to form a PV module with thin strips of metal or conductive polymer formed at low temperature. Such innovations may allow for greater efficiency and flexibility in PV devices when compared to conventional solar cells.

Abstract: Methods and apparatus are provided for converting electromagnetic radiation, such as solar energy, into electric energy with increased efficiency when compared to conventional solar cells. A photovoltaic (PV) unit, according to embodiments of the invention, may have a very thin absorber layer produced by epitaxial lift-off (ELO), all electrical contacts positioned on the back side of the PV device to avoid shadowing, and/or front side and back side light trapping employing a diffuser and a reflector to increase absorption of the photons impinging on the front side of the PV unit. Several PV units may be combined into PV banks, and an array of PV banks may be connected to form a PV module with thin strips of metal or conductive polymer applied at low temperature. Such innovations may allow for greater efficiency and flexibility in PV devices when compared to conventional solar cells.

Abstract: Methods and apparatus are provided for converting electromagnetic radiation, such as solar energy, into electric energy with increased efficiency when compared to conventional solar cells. In one embodiment of a photovoltaic (PV) device, the PV device generally includes an n-doped layer and a p+-doped layer adjacent to the n-doped layer to form a p-n layer such that electric energy is created when electromagnetic radiation is absorbed by the p-n layer. The n-doped layer and the p+-doped layer may compose an absorber layer having a thickness less than 500 nm. Such a thin absorber layer may allow for greater efficiency and flexibility in PV devices when compared to conventional solar cells.

Abstract: Methods and apparatus are provided for converting electromagnetic radiation, such as solar energy, into electric energy with increased efficiency when compared to conventional solar cells. A photovoltaic (PV) device may incorporate front side and/or back side light trapping techniques in an effort to absorb as many of the photons incident on the front side of the PV device as possible in the absorber layer. The light trapping techniques may include a front side antireflective coating, multiple window layers, roughening or texturing on the front and/or the back sides, a back side diffuser for scattering the light, and/or a back side reflector for redirecting the light into the interior of the PV device. With such light trapping techniques, more light may be absorbed by the absorber layer for a given amount of incident light, thereby increasing the efficiency of the PV device.

Abstract: Methods and apparatus are provided for converting electromagnetic radiation, such as solar energy, into electric energy with increased efficiency when compared to conventional solar cells. A photovoltaic (PV) unit, according to embodiments of the invention, may have a very thin absorber layer produced by epitaxial lift-off (ELO), all electrical contacts positioned on the back side of the PV device to avoid shadowing, and/or front side and back side light trapping employing a diffuser and a reflector to increase absorption of the photons impinging on the front side of the PV unit. Several PV units may be combined into PV banks, and an array of PV banks may be connected to form a PV module with thin strips of metal or conductive polymer applied at low temperature. Such innovations may allow for greater efficiency and flexibility in PV devices when compared to conventional solar cells.

Abstract: Methods and apparatus are provided for converting electromagnetic radiation, such as solar energy, into electric energy with increased efficiency when compared to conventional solar cells. A photovoltaic (PV) unit, according to embodiments of the invention, may have a very thin absorber layer produced by epitaxial lift-off (ELO), all electrical contacts positioned on the back side of the PV device to avoid shadowing, and/or front side and back side light trapping employing a diffuser and a reflector to increase absorption of the photons impinging on the front side of the PV unit. Several PV units may be combined into PV banks, and an array of PV banks may be connected to form a PV module with thin strips of metal or conductive polymer applied at low temperature. Such innovations may allow for greater efficiency and flexibility in PV devices when compared to conventional solar cells.

Abstract: Epitaxial lift off systems and methods are presented. In one embodiment a tape is disposed on the opposite side of the epitaxial material than the substrate is used to hold the epitaxial material during the etching and removal steps of the ELO process. In various embodiments, the apparatus for removing the ELO film from the substrates without damaging the ELO film may include an etchant reservoir, substrate handling and tape handling mechanisms, including mechanisms to manipulate (e.g., cause tension, peel, widen the etch gap, etc.) the lift off component during the lift off process.

Abstract: Methods and apparatus are provided for converting electromagnetic radiation, such as solar energy, into electric energy with increased efficiency when compared to conventional solar cells. A photovoltaic (PV) device may incorporate front side and/or back side light trapping techniques in an effort to absorb as many of the photons incident on the front side of the PV device as possible in the absorber layer. The light trapping techniques may include a front side antireflective coating, multiple window layers, roughening or texturing on the front and/or the back sides, a back side diffuser for scattering the light, and/or a back side reflector for redirecting the light into the interior of the PV device. With such light trapping techniques, more light may be absorbed by the absorber layer for a given amount of incident light, thereby increasing the efficiency of the PV device.

Abstract: Methods and apparatus are provided for converting electromagnetic radiation, such as solar energy, into electric energy with increased efficiency when compared to conventional solar cells. In one embodiment of a photovoltaic (PV) device, the PV device generally includes an n-doped layer and a p+-doped layer adjacent to the n-doped layer to form a p-n layer such that electric energy is created when electromagnetic radiation is absorbed by the p-n layer. The n-doped layer and the p+-doped layer may compose an absorber layer having a thickness less than 500 nm. Such a thin absorber layer may allow for greater efficiency and flexibility in PV devices when compared to conventional solar cells.