Provided are optical devices and systems fabricated, at least in part, via printing-based assembly and integration of device components. In specific embodiments the present invention provides light emitting systems, light collecting systems, light sensing systems and photovoltaic systems comprising printable semiconductor elements, including large area, high performance macroelectronic devices. Optical systems of the present invention comprise semiconductor elements assembled, organized and/or integrated with other device components via printing techniques that exhibit performance characteristics and functionality comparable to single crystalline semiconductor based devices fabricated using conventional high temperature processing methods. Optical systems of the present invention have device geometries and configurations, such as form factors, component densities, and component positions, accessed by printing that provide a range of useful device functionalities. Optical systems of the present invention include devices and device arrays exhibiting a range of useful physical and mechanical properties including flexibility, shapeability, conformability and stretchablity.

Provided are optical devices and systems fabricated, at least in part, via printing-based assembly and integration of device components. In specific embodiments the present invention provides light emitting systems, light collecting systems, light sensing systems and photovoltaic systems comprising printable semiconductor elements, including large area, high performance macroelectronic devices. Optical systems of the present invention comprise semiconductor elements assembled, organized and/or integrated with other device components via printing techniques that exhibit performance characteristics and functionality comparable to single crystalline semiconductor based devices fabricated using conventional high temperature processing methods. Optical systems of the present invention have device geometries and configurations, such as form factors, component densities, and component positions, accessed by printing that provide a range of useful device functionalities. Optical systems of the present invention include devices and device arrays exhibiting a range of useful physical and mechanical properties including flexibility, shapeability, conformability and stretchablity.

Provided are optical devices and systems fabricated, at least in part, via printing-based assembly and integration of device components. In specific embodiments the present invention provides light emitting systems, light collecting systems, light sensing systems and photovoltaic systems comprising printable semiconductor elements, including large area, high performance macroelectronic devices. Optical systems of the present invention comprise semiconductor elements assembled, organized and/or integrated with other device components via printing techniques that exhibit performance characteristics and functionality comparable to single crystalline semiconductor based devices fabricated using conventional high temperature processing methods. Optical systems of the present invention have device geometries and configurations, such as form factors, component densities, and component positions, accessed by printing that provide a range of useful device functionalities. Optical systems of the present invention include devices and device arrays exhibiting a range of useful physical and mechanical properties including flexibility, shapeability, conformability and stretchablity.

An energy conversion device comprises at least two thin film photovoltaic cells fabricated separately and joined by wafer bonding. The cells are arranged in a hierarchical stack of decreasing order of their energy bandgap from top to bottom. Each of the thin film cells has a thickness in the range from about 0.5 m to about 10 m. The photovoltaic cell stack is mounted upon a thick substrate composed of a material selected from silicon, glass, quartz, silica, alumina, ceramic, metal, graphite, and plastic. Each of the interfaces between the cells comprises a structure selected from a tunnel junction, a heterojunction, a transparent conducting oxide, and an alloying metal grid; and the top surface and/or the lower surface of the energy conversion device may contain light-trapping means.

An energy conversion device comprises at least two thin film photovoltaic cells fabricated separately and joined by wafer bonding. The cells are arranged in a hierarchical stack of decreasing order of their energy bandgap from top to bottom. Each of the thin film cells has a thickness in the range from about 0.5 m to about 10 m. The photovoltaic cell stack is mounted upon a thick substrate composed of a material selected from silicon, glass, quartz, silica, alumina, ceramic, metal, graphite, and plastic. Each of the interfaces between the cells comprises a structure selected from a tunnel junction, a heterojunction, a transparent conducting oxide, and an alloying metal grid; and the top surface and/or the lower surface of the energy conversion device may contain light-trapping means.

A transducer to convert optical energy to electrical energy. The transducer or photo-transducer has a base layer which has a group of connecting elements formed therein at separations which are increasing with the distance away from an emitter layer formed atop the base layer. The connecting elements separate and electrically connect the base layer into base segments, the base segments having increasing thicknesses with the distance away from the emitter layer. The photo-transducer generates an output voltage that is greater than the input light photovoltage. The photo-transducer output voltage is proportional to the number of connecting elements formed in the base layer.

Systems and methods for advanced ultra-high-performance InP solar cells are provided. In one embodiment, an InP photovoltaic device comprises: a p-n junction absorber layer comprising at least one InP layer; a front surface confinement layer; and a back surface confinement layer; wherein either the front surface confinement layer or the back surface confinement layer forms part of a High-Low (HL) doping architecture; and wherein either the front surface confinement layer or the back surface confinement layer forms part of a heterointerface system architecture.

A photovoltaic cell is provided that can be used under high levels of solar concentration (1000 suns). The present cell includes at least one junction produced on a substrate based on gallium antimonide, the at least one junction having two alloys based on an antimonide material (Ga.sub.1-xAl.sub.xAs.sub.ySb.sub.1-y) lattice-matched on the substrate GaSb. If there are several junctions, two neighbouring junctions are separated by a tunnel junction.

System and method of providing a photovoltaic (PV) cell having a cushion layer to alleviate stress impact between a front metal contact and a thin film PV layer. A cushion layer is disposed between an extraction electrode and a photovoltaic (PV) surface. The cushion layer is made of a nonconductive material and has a plurality of vias filled with a conductive material to provide electrical continuity between the bus bar and the PV layer. The cushion layer may be made of a flexible material preferably with rigidity that matches the substrate. Thus, the cushion layer can effectively protect the PV layer from physical damage due to tactile contact with the front metal contact.

A single-step wet etch process is provided to isolate multijunction solar cells on semiconductor substrates, wherein the wet etch chemistry removes semiconductor materials nonselectively without a major difference in etch rate between different heteroepitaxial layers. The solar cells thus formed comprise multiple heterogeneous semiconductor layers epitaxially grown on the semiconductor substrate.