A radiation window foil for an X-ray radiation window comprises a mesh that defines a number of openings (902), said mesh having a first side surface (903) and a second side surface (904). A layer (906) spans said openings. Said layer (906) is on the first side of the mesh but spans said openings at a level closer to the second side surface (904) of the mesh than the first side surface (903) of the mesh.

Methods are described that include reacting a starting nanocrystal that includes a starting nanocrystal core and a covalently bound surface species to create an ion-exchangeable (IE) nanocrystal that includes a surface charge and a first ion-exchangeable (IE) surface ligand ionically bound to the surface charge, where the starting nanocrystal core includes a group IV element.

Disclosed is an avalanche photodiode using a silicon nanowire, including a first silicon nanowire formed of silicon (Si), a first conductive region formed by doping one surface of the first silicon nanowire with a first dopant, and a second conductive region formed by doping one surface of the first silicon nanowire with a second dopant having a conductive type different from that of the first dopant so as to be arranged continuously in a longitudinal direction from the first conductive region, wherein, when the magnitude of a reverse voltage applied to both ends of the first silicon nanowire is equal to or greater than a preset breakdown voltage, avalanche multiplication of inner current occurs due to the incidence of light from the outside.

According to a photodetector includes a first light detection layer and a reflective layer. The first light detection layer has a first surface and a second surface on a side opposite to the first surface. The first light detection layer includes a first light detection area including a p-n junction of a p-type semiconductor layer containing Si and an n-type semiconductor layer containing Si. The reflective layer arranged on a second surface side of the first light detection layer so as to be opposed to the first light detection area. The reflective layer reflects at least part of light in a near-infrared range.

According to example embodiments, an electronic device includes channel layer including a graphene layer electrically contacting a quantum dot layer including a plurality of quantum dots, a first electrode and a second electrode electrically connected to the channel layer, respectively, and a gate electrode configured to control an electric current between the first electrode and the second electrode via the channel layer. A gate insulating layer may be between the gate electrode and the channel layer.

Photodetector structures and methods of manufacture are provided. The method includes forming undercuts about detector material formed on a substrate. The method further includes encapsulating the detector to form airgaps from the undercuts. The method further includes annealing the detector material causing expansion of the detector material into the airgaps.

An optical semiconductor device comprises, on a substrate, a fin of diamond-cubic semiconductor material and, at the base of the fin, a slab of that semiconductor material, in a diamond-hexagonal structure, that extends over the full width of the fin, the slab being configured as an optically active material. This semiconductor material can contain silicon. A method for manufacturing the optical semiconductor device comprises annealing the sidewalls of the fin, thereby inducing a stress gradient along the width of the fin.

A photovoltaic device includes a digital alloy buffer layer including a plurality of alternating layers of semiconductor material. An absorption layer epitaxially is grown on the digital alloy buffer layer, an intrinsic layer is formed on the absorption layer and a doped layer is formed on the intrinsic layer. A conductive contact is formed on the doped layer.

Example embodiments relate to an electronic device having a graphene-semiconductor multi-junction and a method of manufacturing the electronic device. The electronic device includes a graphene layer having at least one graphene protrusion and a semiconductor layer that covers the graphene layer. A side surface of each of the at least one graphene protrusion may be uneven, may have a multi-edge, and may be a stepped side surface. The graphene layer includes a plurality of nanocrystal graphenes. The graphene layer includes a lower graphene layer having a plurality of nanocrystal graphenes and the at least one graphene protrusion that is formed on the lower graphene layer. The semiconductor layer may include a transition metal dichalcogenide (TMDC) layer. Each of the at least one graphene protrusion may include a plurality of nanocrystal graphenes.

A photodiode structure is based on the use of a double junction sensitive to different wavelength bands based on a magnitude of a reverse bias applied to the photodiode. The monolithic integration of a sensor with double functionality in a single chip allows realization of a low cost ultra-compact sensing element in a single packaging useful in many applications which require simultaneous or spatially synchronized detection of optical photons in different spectral regions.