Disclosed herein is a radiation detector comprising: a substrate of an intrinsic semiconductor; a semiconductor single crystal in a recess in the substrate, the semiconductor single crystal having a different composition from the intrinsic semiconductor; a first electrical contact in electrical contact with the semiconductor single crystal; a second electrical contact on or in the substrate, and surrounding the first electrical contact or the semiconductor single crystal, wherein the second electrical contact is electrically isolated from the semiconductor single crystal; wherein the radiation detector is configured to absorb radiation particles incident on the semiconductor single crystal and to generate charge carriers.

A method for producing a CdTe solar cell is provided, wherein at least the following layers are deposited on a glass substrate within a vacuum chamber: a TCO layer acting as a frontal contact; at least one CdTe layer; a thin layer of a chlorine-containing compound, and an electrically conductive layer acting as a return contact. Here, a maximally 20 nm thick passivation layer made from CdS, in which chemically non-bound oxygen is embedded, is deposited on the TCO layer prior to deposition of at least one CdTe-layer.

In a method of cleaning a substrate, a solution including a size-modification material is applied on a substrate, on which particles to be removed are disposed. Size-modified particles having larger size than the particles are generated, from the particles and the size-modification material. The size-modified particles are removed from the substrate.

Nanometer sized materials can be produced by exposing a target to a laser source to remove material from the target and deposit the removed material onto a surface of a substrate to grow a thin film in a vacuum chamber.

Disclosed herein is a radiation detector configured to absorb radiation particles incident on a semiconductor single crystal of the radiation detector and to generate positive charge carriers and negative charge carriers in the semiconductor single crystal. The semiconductor single crystal may be a cadmium zinc telluride (CdZnTe) single crystal or a cadmium telluride (CdTe) single crystal. The radiation detector comprises a first electrical contact in electrical contact with the semiconductor single crystal and a second electrical contact surrounding the first electrical contact or the semiconductor single crystal. The first electrical contact is configured to collect the negative charge carriers. The second electrical contact is configured to cause the positive charge carriers to drift out of the semiconductor single crystal.

A method for annealing an absorber layer is disclosed, the method including contacting a surface of the absorber layer with an annealing material provided as a gel. The annealing material comprises cadmium chloride and a thickening agent. A viscosity of the gel of the annealing material is greater than or equal to 5 millipascal seconds.

A method of making a photovoltaic cell includes providing a metal oxide substrate. The substrate is at least translucent to light. The substrate is directed through a deposition chamber. A semiconductor is deposited over a first major surface of the substrate. The semiconductor includes a polycrystalline p-type layer. The semiconductor is exposed to a chlorine-containing compound or a chlorine molecule. A second electrode layer is provided over the semiconductor.

Described are flexible electronics incorporating a bacterial cellulose paper substrate and methods of making and using the flexible electronics. Example devices disclosed include photovoltaic cells constructed over bacterial cellulose paper substrates.

Solar cell structures comprising a plurality of solar cells, wherein each solar cell is separated from adjacent solar cell via a tunnel junction and/or a resonant tunneling structure (RTS), are described. Solar cells are implemented on Ge, Si, GaN, sapphire, and glass substrates. Each of the plurality of solar cells is at least partially constructed from a cell material which harnesses photons having energies in a predetermined energy range. In one embodiment each solar cell comprises of at least two sub-cells. It also describes a nano-patterned region/layer to implement high efficiency tandem/multi-junction solar cells that reduces dislocation density due to mismatch in lattice constants in the case of single crystalline and/or polycrystalline solar cells. Finally, solar structure could be used as light-emitting diodes when biased in forward biasing mode. The mode of operation could be determined by a programmed microprocessor.

A photo detector comprises a first photo diode configured to capture visible light, a second photo diode configured to capture one of infrared light or ultraviolet light, and an isolation region between the first photo diode and the second photo diode. The photo detector is capable of capturing infrared light and ultraviolet light in addition to visible light.