Provided are a solar cell and a light emitting device with low leakage current and low cost, using ZnO fine particles. A p-type ZnO layer (p-type layer) (14) made primarily of p-type ZnO fine particles (931) is formed. P-side electrodes (16) are formed at a plurality of regions on the p-type layer (14). A thin insulating layer (18) is formed between an n-type layer (13) and the p-type layer (14). In the insulating layer (18), openings are formed at regions A each not overlapping the p-side electrodes (16) and being apart from them in a plan view. In the configuration, by thus making the p-side electrodes (16) apart from the regions A, the length of a current path in the p-type layer (14) can be made substantially larger than the layer thickness. Accordingly, even when n-type ZnO fine particles (932) are incorporated in the p-type layer (14), it is possible to interpose some of the p-type ZnO fine particles (931) along a leakage current path caused by the incorporation, and thereby cut off the current path.

Provided are a solar cell and a light emitting device with low leakage current and low cost, using ZnO fine particles. A p-type ZnO layer (p-type layer) (14) made primarily of p-type ZnO fine particles (931) is formed. P-side electrodes (16) are formed at a plurality of regions on the p-type layer (14). A thin insulating layer (18) is formed between an n-type layer (13) and the p-type layer (14). In the insulating layer (18), openings are formed at regions A each not overlapping the p-side electrodes (16) and being apart from them in a plan view. In the configuration, by thus making the p-side electrodes (16) apart from the regions A, the length of a current path in the p-type layer (14) can be made substantially larger than the layer thickness. Accordingly, even when n-type ZnO fine particles (932) are incorporated in the p-type layer (14), it is possible to interpose some of the p-type ZnO fine particles (931) along a leakage current path caused by the incorporation, and thereby cut off the current path.

A method of synthesis of two-dimensional (2D) nanoflakes comprises the cutting of prefabricated nanoparticles. The method allows high control over the shape, size and composition of the 2D nanoflakes, and can be used to produce material with uniform properties in large quantities. Van der Waals heterostructure devices are prepared by fabricating nanoparticles, chemically cutting the nanoparticles to form nanoflakes, dispersing the nanoflakes in a solvent to form an ink, and depositing the ink to form a thin film.

A photoconductive transducer intended to generate or detect waves in the terahertz frequency domain or in the picosecond pulse domain is provided. The transducer comprises a three-dimensional structure that includes, in this order, a first planar electrode, an array of nano-columns embedded in a layer of resist and a second planar electrode parallel to the first planar electrode. The design of the transducer increases the optical-to-terahertz conversion efficiency by means of photonic and plasmonic resonances and by means of high and homogeneous electric fields. The height of the nano-columns as well as the thickness of the resist range between 100 nanometres and 400 nanometres. The width of the nano-columns is between 100 nanometres and 400 nanometres, the distance between two adjacent nano-columns is between 300 nanometres and 500 nanometres, the nano-columns are made of a III-V semiconductor. The second electrode is transparent, so as to allow the transmission of a laser source towards the photo-absorbing nano-columns.

A photoconductive transducer intended to generate or detect waves in the terahertz frequency domain or in the picosecond pulse domain is provided. The transducer comprises a three-dimensional structure that includes, in this order, a first planar electrode, an array of nano-columns embedded in a layer of resist and a second planar electrode parallel to the first planar electrode. The design of the transducer increases the optical-to-terahertz conversion efficiency by means of photonic and plasmonic resonances and by means of high and homogeneous electric fields. The height of the nano-columns as well as the thickness of the resist range between 100 nanometres and 400 nanometres. The width of the nano-columns is between 100 nanometres and 400 nanometres, the distance between two adjacent nano-columns is between 300 nanometres and 500 nanometres, the nano-columns are made of a III-V semiconductor. The second electrode is transparent, so as to allow the transmission of a laser source towards the photo-absorbing nano-columns.

An integrated tandem solar cell includes a first solar cell including a rear electrode, a light absorption layer disposed on the rear electrode, and a buffer layer disposed on the light absorption layer; a recombination layer including a first transparent conductive layer disposed on the buffer layer; a nanoparticle layer that is transparent and conductive, that is disposed on the first transparent conductive layer, and that planarizes the first solar cell; and a second transparent conductive layer disposed on the nanoparticle layer; and a second solar cell that is a perovskite solar cell including a perovskite layer and that is disposed on and bonded to the second transparent conductive layer of the recombination layer. The recombination layer electrically joins the first and second solar cells and planarizes the first solar cell so that the second solar cell is uniformly deposited in all regions thereof.

A photovoltaic device (10) comprising a photoactive body between two electrodes (contact 1, contact 2). The body comprises semiconductor particles (24) embedded in a semiconductor matrix (22). The particles and matrix are electronically or optically coupled so that charge carriers generated in the particles are transferred directly or indirectly to the matrix. The matrix transports positive charge carriers to one of the electrodes and negative charge carriers to the other electrode. The particles are configured so that they do not form a charge carrier transport network to either of the electrodes and so perform the function of charge carrier generation but not charge carrier transport.

An electronic device may include an infrared sensor with light sources and a quantum film photodetector. The light sources may emit short-wavelength infrared (SWIR) light through a display panel and the photodetector may receive the SWIR light through the panel after reflection off an object. The light sources and an integrated circuit may be mounted to a wall of a sensor module mounted to the panel. The module may include a lens. The photodetector may be disposed onto the rear wall, lens, integrated circuit, or display panel. The photodetector may include multiple types of quantum film to absorb different wavelengths of SWIR light. The SWIR light may pass through the display panel without distorting images emitted by the display panel. Using a quantum film in the photodetector may allow the photodetector to extend across a large surface area without unnecessarily increasing manufacturing cost for the device.

Photovoltaic devices and methods for fabricating a photovoltaic devices. The method includes applying a coating layer that surrounds each of a plurality of silicon particles. The method also includes implanting the plurality of silicon particles into a substrate layer such that an exposed portion of each of the plurality of silicon particles extends away from a surface of the substrate layer. The method further includes removing a portion of the coating layer that is positioned around the exposed portion of each of the plurality of silicon particles. The method also includes placing an insulator layer on the surface of the substrate layer. The method further includes placing a selective carrier transport layer on the exposed portion of each of the plurality of silicon particles.

Disclosed are a functional photoresist for patterning a nanoparticle thin film including nanoparticles on a substate and a method of patterning a nanoparticle thin film using the functional photoresist, wherein the functional photoresist includes a photoactive compound (PAC); and a functional ligand that is bound to the surfaces of the nanoparticles and controls the physical properties of the nanoparticles.