Provided is a multi-junction solar cell in which two or more absorption layers having different bandgaps are stacked on one another. The multi-junction solar cell includes a first cell including a first absorption layer, and a second cell electrically connected in series onto the first cell, wherein the second cell includes a second absorption layer having a higher bandgap compared to the first absorption layer, and a plurality of recesses penetrating through the second absorption layer.

Methods of making a semiconductor layer from nanocrystals are disclosed. A film of nanocrystals capped with a ligand can be deposited onto a substrate; and the nanocrystals can be irradiated with one or more pulses of light. The pulsed light can be used to substantially remove the ligands from the nanocrystals and leave the nanocrystals unsintered or sintered, thereby providing a semiconductor layer. Layered structures comprising these semiconductor layers with an electrode are also disclosed. Devices comprising such layered structures are also disclosed.

According to some embodiments, the present invention provides a novel photovoltaic solar cell system from photovoltaic modules that are vertically arrayed in a stack format using thin film semiconductors selected from among organic and inorganic thin film semiconductors. The stack cells may be cells that are produced in a planar manner, then vertically oriented in an angular form, also termed herein tilted, to maximize the light capturing aspects. The use of a stack configuration system as described herein allows for the use of a variety of electrode materials, such as transparent materials or semitransparent metals. Light concentration can be achieved by using fresnel lens, parabolic mirrors or derivatives of such structures. The light capturing can be controlled by being reflected back and forth in the photovoltaic system until significant quantities of the resonant light is absorbed. Light that passes to the very end and can be reflected back through the device by beveling or capping the end of the device with a different refractive index material, or alternatively using a reflective surface. The contacting between stacked cells can be done in series or parallel. According to some embodiments, the present invention uses a concentrator architecture where the light is channeled into the cells that contain thermal fluid channels (using a transparent fluid such as water) to absorb and hence reduce the thermal energy generation.

Photovoltaic cells, photovoltaic devices, and methods of fabrication are provided. The photovoltaic cells include a transparent substrate to allow light to enter the photovoltaic cell through the substrate, and a light absorption layer associated with the substrate. The light absorption layer has opposite first and second surfaces, with the first surface being closer to the transparent substrate than the second surface. A passivation layer is disposed over the second surface of the light absorption layer, and a plurality of first discrete contacts and a plurality of second discrete contacts are provided within the passivation layer to facilitate electrical coupling to the light absorption layer. A first electrode and a second electrode are disposed over the passivation layer to contact the plurality of first discrete contacts and the plurality of second discrete contacts, respectively. The first and second electrodes may include a photon-reflective material.

A method for fabricating thin-film optoelectronic devices (100), the method comprising: providing a alkali-nondiffusing substrate (110), forming a back-contact layer (120); forming at least one absorber layer (130) made of an ABC chalcogenide material, adding least one and advantageously at least two different alkali metals, and forming at least one front-contact layer (150) wherein one of said alkali metals comprise Rb and/or Cs and where, following forming said front-contact layer, in the interval of layers (470) from back-contact layer (120), exclusive, to front-contact layer (150), inclusive, the comprised amounts resulting from adding alkali metals are, for Rb and/or Cs, in the range of 500 to 10000 ppm and, for the other alkali metals, typically Na or K, in the range of 5 to 2000 ppm and at most 1/2 and at least 1/2000 of the comprised amount of Rb and/or Cs. The method (200) is advantageous for more environmentally-friendly production of photovoltaic devices on flexible substrates with high photovoltaic conversion efficiency and faster production rate.

In the field of energy technology, a CIGS solar cell and a preparation method thereof, are provided. In some embodiments, the method for preparing the CIGS solar cell comprises: forming a back electrode layer and a CIGS layer sequentially on a surface of a substrate; etching a surface of the CIGS layer, and performing cleaning, drying and annealing treatments after the etching is completed; and forming a buffer layer, a window layer and a transparent electrode layer sequentially on a surface of the annealed CIGS layer after the annealing treatment. The CISG solar cell and the preparation method thereof as provided by some embodiments can improve photoelectric conversion performance of the CIGS solar cell and increase conversion efficiency of the CIGS solar cell.

In various embodiments, photovoltaic modules are hermetically sealed by providing a first glass sheet, a photovoltaic device disposed on the first glass sheet, and a second glass sheet, a gap being defined between the first and second glass sheets, disposing a glass powder within the gap, and heating the powder to seal the glass sheets.

The present invention relates to a structure of a solar cell for improving photoelectric conversion efficiency of the solar cell, and a manufacturing method therefor. One aspect of the solar cell according to the present invention relates to a solar cell having a light-absorbing layer formed between two electrodes arranged to face each other, wherein an electrical polarization layer comprising an electrical polarization material forming an inner electrical field is formed between the electrodes and the light-absorbing layer.

The resent invention relates to a method for manufacturing a solar cell, the method comprising the steps of: (a) forming a lower electrode layer on a substrate; (b) forming a CIGS light absorbing layer on the lower electrode layer by supplying a copper precursor to deposit a copper thin film using chemical vapor deposition and then supplying a gallium precursor, an indium precursor, and a first selenium precursor to deposit a gallium thin film and an indium-selenium thin film using chemical vapor deposition; and (c) sequentially forming a buffer layer and a front electrode layer on the CIGS light absorbing layer.

A method (200) for fabricating patterns on the surface of a layer of a device (100), the method comprising: providing at least one layer (130, 230); adding at least one alkali metal (235) comprising Cs and/or Rb; controlling the temperature (2300) of the at least one layer, thereby forming a plurality of self-assembled, regularly spaced, parallel lines of alkali compound embossings (1300, 1305) at the surface of the layer. The method further comprises forming cavities (236, 1300) by dissolving the alkali compound embossings. The method (200) is advantageous for nanopatterning of devices (100) without using templates and for the production of high efficiency optoelectronic thin-film devices (100).