5135 results about "Electron hole" patented technology

A high-efficiency, high-durability organic electroluminescent device, particularly a phosphorescent organic electroluminescent device is provided by using an organic compound of excellent characteristics that exhibits excellent hole-injecting / transporting performance and has high triplet exciton confining capability with an electron blocking ability, and that has high stability in the thin-film state and high luminous efficiency.The organic electroluminescent device includes a pair of electrodes, and a plurality of organic layers sandwiched between the pair of electrodes and including a phosphorescent light-emitting material-containing light emitting layer and a hole transport layer, wherein a compound of the following general formula (1) having a carbazole ring structure is used as a constituent material of the hole transport layer.

A method (and resulting structures) for manufacturing light emitting semiconductor devices. The method includes providing a substrate comprising a surface region and forming a metal layer overlying the surface region of the substrate. In a specific embodiment, the metal layer and the surface region are characterized by a spatial spacing between the metal layer and the substrate to cause a coupling between electron-hole pairs generated in the substrate and a surface plasmon mode at an interface region between the metal layer and the surface region. Additionally, the interface region has a textured characteristic between the surface region and the metal layer. The textured characteristics causes emission of electromagnetic radiation through the surface plasmon mode or like mechanism according to a specific embodiment.

An electroluminescent device comprises a cathode and an anode; and, located therebetween, a light-emitting layer (LEL) comprising at least one hole transporting co-host and at least one electron transporting co-host, together with at least one phosphorescent emitter, and wherein the triplet energy of each of the co-host materials is greater than the triplet energy of the phosphorescent emitter, and further containing an exciton blocking layer comprising a hole transporting material with triplet energy greater or equal to 2.5 eV adjacent the emitting layer on the anode side. The invention provides devices that emit light with high luminous efficiency at low voltage.

An organic electroluminescent element comprising a cathode, an anode, an intermediate unit arranged between a cathode and an anode, a first light emitting unit arranged between a cathode and an intermediate unit, and a second light emitting unit arranged between an anode and an intermediate unit, wherein an electron extracting layer for extracting an electron from an adjacent layer adjoining a cathode side is provided in an intermediate unit, an absolute value of an energy level of a lowest unoccupied molecular orbital (LUMO) of an electron extracting layer |LUMO(A)|, and an absolute value of an energy level of a highest occupied molecular orbital (HOMO) of the adjacent layer |HOMO(B)| are in the relationship of |HOMO(B)|−|LUMO(A)|≦1.5 eV, and an intermediate unit supplies a hole generated by extraction of an electron from an adjacent layer by an electron extracting layer and, at the same time, supplies the extracted electron to a second light emitting unit.

An organic light-emitting element having high efficiency and long lifetime is provided. An organic light-emitting body is provided which includes a host having a high electron-transport property (n-type host), a host having a high hole-transport property (p-type host), and a guest such as an iridium complex and in which the n-type host and the p-type host are located so as to be adjacent to each other. When an electron and a hole are injected to such a light-emitting body, the electron is trapped by the n-type host and the hole is trapped by the p-type host. Then, both the electron and the hole are injected to the guest, and thus the guest is brought into an excited state. In this process, less thermal deactivation occurs and the working rate of the guest is high; thus, highly efficient light emission can be obtained.

The method for forming a multilayer structure on a substrate comprises providing a stack successively comprising an electron hole blocking layer, a first layer made from N-doped semiconductor material having a dopant concentration greater than or equal to 1018 atoms / cm3 or P-doped semiconductor material, and a second layer made from semiconductor material of different nature. A lateral electric contact pad is made between the first layer and the substrate, and the material of the first layer is subjected to anodic treatment in an electrolyte.

An organic electroluminescence display unit includes: a lower electrode for each device; a first hole injection / transport layer provided on the lower electrode for each device; a second organic light emitting layer of the first color provided on the first hole injection / transport layer for the second organic electroluminescence device; a second hole injection / transport layer provided on the entire surfaces of the second organic light emitting layer and the first hole injection / transport layer for the first organic electroluminescence device, and being made of a low molecular material; a blue first organic light emitting layer provided on the entire surface of the second hole injection / transport layer; and an electron injection / transport layer having at least one of electron injection characteristics and electron transport characteristics, and an upper electrode that are provided in sequence on the entire surface of first organic light emitting layer.

To provide a light-emitting element with high light emission efficiency, a long lifetime, and reduced driving voltage. To provide a light-emitting element including an anode, a cathode, and a plurality of light-emitting layers which are in contact with each other so that a stacked structure is formed, between the anode and the cathode, in which the plurality of light-emitting layers are formed with a first light-emitting layer which is close to the anode and a second light-emitting layer which is close to the cathode, the first light-emitting layer and the second light-emitting layer each include a host material, a hole-transporting material, and a light-emitting material, and the concentration of the hole-transporting material in the first light-emitting layer is higher than the concentration of the hole-transporting material in the second light-emitting layer.

The present invention provides an organic electroluminescent element which is superior in luminance, reliability, and thermal stability and is capable of selectively emitting light with comparative long wavelengths such as red and good color purity and a light-emitting device or display device incorporated therewith. The organic electroluminescent element consists of a glass substrate (1), an anode (2), a hole transporting layer (10), an emitting layer (11), an electron transporting layer (12), and a cathode (3), which are sequentially laminated on top of the other. The emitting layer (11) is formed from a mixture composed of at least one species of the styryl compound represented by the general formula [I] below and a material with charge transporting capability. Y—CH═CH—X   General formula [I](where X denotes an aryl group (such as phenyl group) which has a substituent group (such as cyano group and methyl group), and Y denotes a group having a skeleton of aminophenyl group or the like.)

An organic light-emitting device comprising an anode; a cathode; a hole-transporting layer disposed between the anode and the cathode; a phosphorescent light-emitting layer disposed between the hole-transporting layer and the cathode, wherein the phosphorescent light-emitting layer includes at least one host and at least one phosphorescent dopant; a first exciton-blocking layer disposed between the hole-transporting layer and the phosphorescent light-emitting layer; wherein the first exciton-blocking layer has a triplet energy greater than the triplet energy of the host in the phosphorescent light-emitting layer; and a second exciton-blocking layer disposed between the first exciton-blocking layer and the phosphorescent light-emitting layer, wherein the second exciton-blocking layer is in contact with the phosphorescent light-emitting layer, and wherein the second exciton-blocking layer has a triplet energy less than the triplet energy of the first exciton-blocking layer.

Embodiments of the present invention involve photovoltaic (PV) cells comprising a semiconducting nanorod-nanocrystal-polymer hybrid layer, as well as methods for fabricating the same. In PV cells according to this invention, the nanocrystals may serve both as the light-absorbing material and as the heterojunctions at which excited electron-hole pairs split.

A tandem OLED includes an anode and a cathode. The OLED also includes at least two electroluminescent units disposed between the anode and the cathode, wherein each of the electroluminescent units includes at least one hole -transporting layer and one organic light-emitting layer. An intermediate connector is disposed between adjacent electroluminescent units, wherein the intermediate connector includes an n-doped organic layer and an electron-accepting layer, the electron-accepting layer being disposed closer to the cathode than the n-doped organic layer, and wherein the electron-accepting layer includes one or more organic materials, each having a reduction potential greater than −0.5 V vs. a Saturated Calomel Electrode, and wherein the one or more organic materials constitute more than 50% by volume of the electron-accepting layer.

An organic photoelectric conversion element comprises: a pair of electrodes; an organic photoelectric conversion layer arranged between the pair of electrodes; and an positive hole blocking layer arranged between one of the pair of electrodes and the organic photoelectric conversion layer, wherein an ionization potential of the positive hole blocking layer is larger than a work function of the adjoining electrode by 1.3 eV or more, and wherein an electron affinity of the positive hole blocking layer is equal to or larger than that of the adjoining organic photoelectric conversion layer. An electron blocking layer may be arranged between the other one of the pair of electrodes and the organic photoelectric conversion layer, wherein its electron affinity is smaller than a work function of the adjoining electrode by 1.3 eV or more, and its ionization potential is equal to or smaller than that of the adjoining organic photoelectric conversion layer.

Subwavelength random and periodic microscopic structures are used to enhance light absorption and tolerance for ionizing radiation damage of thin film and photodetectors. Diffractive front surface microscopic structures scatter light into oblique propagating higher diffraction orders that are effectively trapped within the volume of the photovoltaic material. For subwavelength periodic microscopic structures etched through the majority of the material, enhanced absorption is due to waveguide effect perpendicular to the surface thereof. Enhanced radiation tolerance of the structures of the present invention is due to closely spaced, vertical sidewall junctions that capture a majority of deeply generated electron-hole pairs before they are lost to recombination. The separation of these vertical sidewall junctions is much smaller than the minority carrier diffusion lengths even after radiation-induced degradation. The effective light trapping of the structures of the invention compensates for the significant removal of photovoltaic material and substantially reduces the weight thereof for space applications.

An organic electroluminescent (EL) element includes at least a positive hole transport layer, a light emitting layer and an electron transport layer between at least a pair of electrodes, wherein the light emitting layer contains therein at least two light emitting materials having different Ea values or Ip values and emitting phosphorescence having the same color as each other, and among the two light emitting materials, a light emitting material having a larger Ea value or Ip value is contained at a higher density in a region of the light emitting layer in the vicinity of the positive hole transport layer, while a light emitting material having a smaller Ea value or Ip value is contained at a higher density in a region of the light emitting layer in the vicinity of the electron transport layer.

A radiation sensor including a scintillation layer configured to emit photons upon interaction with ionizing radiation and a photodetector including in order a first electrode, a photosensitive layer, and a photon-transmissive second electrode disposed in proximity to the scintillation layer. The photosensitive layer is configured to generate electron-hole pairs upon interaction with a part of the photons. The radiation sensor includes pixel circuitry electrically connected to the first electrode and configured to measure an imaging signal indicative of the electron-hole pairs generated in the photosensitive layer and a planarization layer disposed on the pixel circuitry between the first electrode and the pixel circuitry such that the first electrode is above a plane including the pixel circuitry. A surface of at least one of the first electrode and the second electrode at least partially overlaps the pixel circuitry and has a surface inflection above features of the pixel circuitry. The surface inflection has a radius of curvature greater than one half micron.

A photocatalytic reactor, capable of generating an electric current by consumption of a fuel containing organic material, comprises a direct oxidation fuel cell including an anode and a cathode. The anode is a photocatalysis-assisted anode which comprises a photocatalyst on a surface of an electrically-conductive substrate so arranged as to be receptive to light. A light-transmissive proton-conductive membrane is arranged between the anode and the cathode, such that light passes through said membrane as a final stage in the optical path to the photocatalyst. The photocatalyst promotes oxidation of organic material and generates electron-hole pairs. The reactor, configured to support multiple cells in a stacked array, is provided with inlet(s) for introducing said fuel and connector(s) for connection to an external electrical circuit.

A method of operating a solar cell is provided in which strain balanced multiple quantum well stacks containing greater than 30 quantum wells disposed between bulk semi-conductor regions having a band gap differences between the deepest well of the stack and the bulk semi-conducting region of greater than 60 mev is irradiated with radiation having an intensity of greater than 100 suns. Photons are absorbed with and outside of the quantum well stack to generate electron hole pairs recombination of electrons and holes is substantially only via a radiative recombination mechanism.

An OLED device comprises, in sequence, an anode, a light-emitting layer that comprises a phosphorescent light-emitting organometallic compound, a hole-blocking layer, and a cathode, and between the hole-blocking layer and the cathode, a further layer containing: a) a first compound that has the lowest LUMO value of the compounds in the layer, the amount being greater than or equal to 10% by volume and less than 100% by volume of the layer; b) at least one second compound that is a low voltage electron transport material, exhibiting a higher LUMO value than the first compound, the total amount of said compound(s) being less than or equal to 90% by volume and more than 0% by volume of the layer. Such a device provides improved drive voltage.

A method of forming a solar cell, the method comprising: providing a semiconducting wafer having a pre-doped region; performing a first ion implantation of a dopant into the semiconducting wafer to form a first doped region over the pre-doped region, wherein the first ion implantation has a concentration-versus-depth profile; and performing a second ion implantation of a dopant into the semiconducting wafer to form a second doped region over the pre-doped region, wherein the second ion implantation has a concentration-versus-depth profile different from that of the first ion implantation, wherein at least one of the first doped region and the second doped region is configured to generate electron-hole pairs upon receiving light, and wherein the first and second ion implantations are performed independently of one another.

An organic electroluminescent device comprising a light-emitting layer between a pair of electrodes, the light-emitting layer comprising a mixture of a hole-transporting material consisting of a tertiary amine compound, an electron-transporting material and a light-emitting additive material, in which the tertiary amine compound has two or more oxidation potentials determined by a cyclic voltammetry wherein a potential difference between the first oxidation potential and the second oxidation potential in the oxidation potentials is 0.22V or more, and a glass transition temperature of at least 100° C., and the electron-transporting material has a glass transition temperature of at least 100° C.

Provided are quantum dots having a gradual composition gradient shell structure which have an improvedluminous efficiency and optical stability, and a method of manufacturing the quantum dots in a short amount of time at low cost. In the method, the quantum dots can be manufactured in a short amount of time at low cost using a reactivity difference between semiconductor precursors, unlike in uneconomical and inefficient conventional methods where shells areformed after forming cores and performing cleaning and redispersion processes. Also, formation of the cores is followed by formation of shells having a composition gradient. Thus, even if the shells are formed to a large thickness, the lattice mismatch between cores and shells is relieved. Furthermore, on the basis of the funneling concept, electrons and holes generated in the shells are transferred to the cores to emit light, thereby obtaining a high luminous efficiency of 80% or more. The quantum dot structure is not limited to Group II-IV semiconductor quantum dots but can be applied to other semiconductors quantum dots, such as Group III-V semiconductors quantum dots and Group IV-IV semiconductors quantum dots. Also, the manufacturing method can be utilized in the development of semiconductor quantum dots having different physical properties, and in various other fields.

A light emitting heterostructure and / or device in which the light generating structure is contained within a potential well is provided. The potential well is configured to contain electrons, holes, and / or electron and hole pairs within the light generating structure. A phonon engineering approach can be used in which a band structure of the potential well and / or light generating structure is designed to facilitate the emission of polar optical phonons by electrons entering the light generating structure. To this extent, a difference between an energy at a top of the potential well and an energy of a quantum well in the light generating structure can be resonant with an energy of a polar optical phonon in the light generating structure material. The energy of the quantum well can comprise an energy at the top of the quantum well, an electron ground state energy, and / or the like.

Phosphorescent OLEDs having a double doped-layer structure wherein the OLEDs include a hole transporting layer (HTL) having a phosphorescent material doped therein, and an electron transporting layer (ETL) having the same phosphorescent material doped therein. Typically, these phosphorescent OLEDs have an anode, a first HTL over the anode, a second HTL that is doped with a phosphorescent material over the first HTL, a first ETL that is doped with a phosphorescent material over the second HTL, a second ETL over the first ETL, and a cathode over the second ETL. These phosphorescent OLEDs preferably include blue phosphorescent OLEDs with high efficiency levels.

A method of synthesizing a doped carbonaceous material includes mixing a carbon precursor material with at least one dopant to form a homogeneous / heterogeneous mixture; and subjecting the mixture to pyrolysis in an inert atmosphere to obtain the doped carbonaceous material. A method of purifying water includes providing an amount of the doped carbonaceous material in the water as a photocatalyst; and illuminating the water containing the doped carbonaceous material with visible light such that under visible light illumination, the doped carbonaceous material generates excitons (electron-hole pairs) and has high electron affinity, which react with oxygen and water adsorbed on its surface forming reactive oxygen species (ROS), such as hydroxyl radicals and superoxide radicals, singlet oxygen, hydrogen peroxide, that, in turn, decompose pollutants and micropollutants.

An optical resonator type organic electroluminescent element has a multilayered film mirror 30, a transparent electrode 12, an electron hole transportation layer 14 and a luminescent layer 16 configuring an organic layer, and a metallic electrode mirror 20, formed on a glass substrate 10. The optical resonator type organic electroluminescent element amplifies a specific wavelength (especially, in a range of about 30 nm toward a shorter wavelength side from a luminescence peak wavelength of the organic layer) in luminescence light by a minute optical resonator, which comprises the multilayered film mirror 30 and the metallic electrode mirror 20. It is determined that the minute optical resonator has an optical length L which is twice as long as a resonance wavelength, the organic layer has a thickness of 100 nm or more, and the transparent electrode has a thickness of 50 nm or more or a thickness so to have a sheet resistance of 30 OMEGA / square or less. Thus, the transparent electrode can be prevented from generating heat even when a large current is caused to flow into it, and the element characteristics can be reliably prevented from being deteriorated. Moreover, the reliability of this element can be improved because the organic layer containing the luminescent layer has a sufficient thickness.

The fabrication of unipolar light emitting devices (ULEDs) based on III-nitride semiconductors is disclosed using an effective "p-n junction" between two n-type III-nitride semiconductor superlattices. Such a device works like a usual light emitting diode at forward bias but the radiation arises not due to recombination of electrons and holes but due to electron transitions from a shallow sub-band superlattice into a deep sub-band superlattice.

The invention relates to a solar cell containing a semiconductor (1) with an intermediate band (2) that is half filled with electrons, located between two layers of ordinary n type (3) and p type (4) semiconductors. When lighted, electron-hole pairs are formed either by a photon that absorbs the necessary energy (5) or by two photons (6,7) that absorb less energy which pump an electron from the valence band to the intermediate band (8) and from the latter to the conductance band (9). An electrical current is generated that exits on the p side and returns via the n side. The n and p layers also prevent the intermediate band from contacting the outer metal connections, which would have resulted in a short-circuit. Said cell converts solar energy into electricity in a more efficient manner than conventional cells and contributes to improvement of the photovoltaic devices.

A phosphorescent-emitting layer contains a phosphorescent host and a phosphorescent dopant for providing phosphorescence, and a fluorescent-emitting layer contains a fluorescent host and a fluorescent dopant for providing fluorescence. A charge blocking layer blocks electrons injected into the fluorescent host of the fluorescent-emitting layer from being injected toward the charge blocking layer from the fluorescent-emitting layer, and also injects holes into the fluorescent-emitting layer from the phosphorescent-emitting layer. A triplet energy gap EgPD of the phosphorescent dopant of the phosphorescent-emitting layer, a triplet energy gap EgEB of the charge blocking layer and a triplet energy gap EgFH of the fluorescent host of the fluorescent-emitting layer satisfy the following formula (1).EgPD<EgEB≦EgFH   (1)