[Problem] The present invention provides a method for bonding semiconductor elements while assuring excellent electric conductivity and transparency at an interface, and a junction structure according to the bonding method. The present invention also provides a method for bonding semiconductor elements wherein excellent electric conductivity is assured at an interface and optical characteristics favorable for element characteristics can be designed, and a junction structure according to the bonding method. [Solution] Electrically conductive nano particles which are not covered with organic molecules are arrayed on a surface of one semiconductor element without causing optical loss, and another semiconductor element is pressure-bonded thereagainst.

A method for manufacturing a two terminal or three terminal tandem solar cell comprising a silicon-based bottom solar cell and a thin-film top solar cell; the method comprising: providing a silicon substrate with a front surface and a rear surface, carrying out a sequence of steps comprising: creating on the front surface a carrier extracting layer stack comprising at least a carrier extracting layer formed on or in the front surface of the substrate, creating on the rear surface a passivating coating layer comprising deposition of a first AlO.sub.x layer, creating sacrificial layer stack comprising a second AlO.sub.x layer on the carrier extracting layer stack on the front surface; creating metal-based electrical contacts on the rear surface, including an annealing step; removing the sacrificial layer stack from the carrier extracting layer stack, and creating the thin film top solar cell on the carrier extracting layer stack.

A method for manufacturing a two terminal or three terminal tandem solar cell comprising a silicon-based bottom solar cell and a thin-film top solar cell; the method comprising: providing a silicon substrate with a front surface and a rear surface, carrying out a sequence of steps comprising: creating on the front surface a carrier extracting layer stack comprising at least a carrier extracting layer formed on or in the front surface of the substrate, creating on the rear surface a passivating coating layer comprising deposition of a first AlO.sub.x layer, creating sacrificial layer stack comprising a second AlO.sub.x layer on the carrier extracting layer stack on the front surface; creating metal-based electrical contacts on the rear surface, including an annealing step; removing the sacrificial layer stack from the carrier extracting layer stack, and creating the thin film top solar cell on the carrier extracting layer stack.

A method of forming a photovoltaic device that includes ion implanting a first conductivity type dopant into first regions of a semiconductor layer of an SOI substrate, wherein the first regions are separated by a first pitch; and ion implanting a second conductivity type dopant into second regions of the semiconductor layer of the SOI substrate. The second regions are separated by a second pitch. Each second conductivity type implanted region of the second regions is in direct contact with first conductivity type implanted region of the first regions to provide a plurality of p-n junctions, and adjacent p-n junctions are separated by an intrinsic portion of the semiconductor layer to provide P-I-N cells that are horizontally oriented.

A method of forming a photovoltaic device that includes ion implanting a first conductivity type dopant into first regions of a semiconductor layer of an SOI substrate, wherein the first regions are separated by a first pitch; and ion implanting a second conductivity type dopant into second regions of the semiconductor layer of the SOI substrate. The second regions are separated by a second pitch. Each second conductivity type implanted region of the second regions is in direct contact with first conductivity type implanted region of the first regions to provide a plurality of p-n junctions, and adjacent p-n junctions are separated by an intrinsic portion of the semiconductor layer to provide P-I-N cells that are horizontally oriented.

A solar cell that capable of improving light utilization efficiency is disclosed. The solar cell comprises I-VII compound photovoltaic layer, silicon photovoltaic layer, first electrode and second electrode. The I-VII compound photovoltaic layer comprises first and second type I-VII compound layers. The first and second type I-VII compound layer have first and second type impurities, respectively. The second type I-VII compound layer is disposed under the first type I-VII compound layer. The silicon photovoltaic layer comprises first and second type silicon layers. The first and second type silicon layers have first and second type dopants, respectively. The first type and second type silicon layers are disposed under the second type I-VII compound layer and the first type silicon layer, respectively. The first and second electrodes are formed under the second type silicon layer and on a portion of the first type I-VII compound layer, respectively.

A solar cell that capable of improving light utilization efficiency is disclosed. The solar cell comprises I-VII compound photovoltaic layer, silicon photovoltaic layer, first electrode and second electrode. The I-VII compound photovoltaic layer comprises first and second type I-VII compound layers. The first and second type I-VII compound layer have first and second type impurities, respectively. The second type I-VII compound layer is disposed under the first type I-VII compound layer. The silicon photovoltaic layer comprises first and second type silicon layers. The first and second type silicon layers have first and second type dopants, respectively. The first type and second type silicon layers are disposed under the second type I-VII compound layer and the first type silicon layer, respectively. The first and second electrodes are formed under the second type silicon layer and on a portion of the first type I-VII compound layer, respectively.

A method for fabricating a device with integrated photovoltaic cells includes supporting a semiconductor substrate on a first handle substrate and doping the semiconductor substrate to form doped alternating regions with opposite conductivity. A doped layer is formed over a first side the semiconductor substrate. A conductive material is patterned over the doped layer to form conductive islands such that the conductive islands are aligned with the alternating regions to define a plurality of photovoltaic cells connected in series on a monolithic structure.

A method for fabricating a device with integrated photovoltaic cells includes supporting a semiconductor substrate on a first handle substrate and doping the semiconductor substrate to form doped alternating regions with opposite conductivity. A doped layer is formed over a first side the semiconductor substrate. A conductive material is patterned over the doped layer to form conductive islands such that the conductive islands are aligned with the alternating regions to define a plurality of photovoltaic cells connected in series on a monolithic structure.

A method of fabricating a multi-junction photosensitive device is provided. The method may include fabricating at least two photoactive layers, wherein at least one photoactive layer is fabricated on a transparent substrate, and at least one photoactive layer is fabricated on a reflective substrate, patterning at least one optical filter layer on at least one photoactive layer fabricated on a transparent substrate, and bonding the at least two photoactive layers using cold weld or van der Waals bonding. A multi-junction photosensitive device is also provided. The device may have at least two photoactive layers, and at least one optical filter layer, wherein at least two layers are bonded using cold weld or van der Waals bonding. The optical filter layer may be a Distributed Bragg Reflector.