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 light emitting device includes a first active layer on a substrate, a current spreading length, and a plurality of mesa regions on the first active layer. At least a first portion of the first active layer can comprise a first electrical polarity. Each mesa region can include, at least a second portion of the first active layer, a light emitting region on the second portion of the first active layer with a dimension parallel to the substrate smaller than twice the current spreading length, and a second active layer on the light emitting region. The light emitting region can be configured to emit light with a target wavelength from 200 nm to 300 nm. At least a portion of the second active layer can comprise a second electrical polarity.

A semiconductor nanocrystal particle, a production method thereof, and a light emitting device including the same. The semiconductor nanocrystal particle includes a core including a first semiconductor nanocrystal, a first shell surrounding the core, the first shell including a second semiconductor nanocrystal including a different composition from the first semiconductor nanocrystal, a second shell surrounding the first shell, the second shell including a third semiconductor nanocrystal including a different composition from the second semiconductor nanocrystal, wherein the first semiconductor nanocrystal includes zinc and sulfur; wherein the third semiconductor nanocrystal includes zinc and sulfur; wherein an energy bandgap of the second semiconductor nanocrystal is less than an energy bandgap of the first semiconductor nanocrystal and less than an energy bandgap of the third semiconductor nanocrystal; and wherein the semiconductor nanocrystal particle does not include cadmium.

A semiconductor nanocrystal particle, a production method thereof, and a light emitting device including the same. The semiconductor nanocrystal particle includes a core including a first semiconductor nanocrystal, a first shell surrounding the core, the first shell including a second semiconductor nanocrystal including a different composition from the first semiconductor nanocrystal, a second shell surrounding the first shell, the second shell including a third semiconductor nanocrystal including a different composition from the second semiconductor nanocrystal, wherein the first semiconductor nanocrystal includes zinc and sulfur; wherein the third semiconductor nanocrystal includes zinc and sulfur; wherein an energy bandgap of the second semiconductor nanocrystal is less than an energy bandgap of the first semiconductor nanocrystal and less than an energy bandgap of the third semiconductor nanocrystal; and wherein the semiconductor nanocrystal particle does not include cadmium.

A semiconductor nanocrystal particle including a core including a first semiconductor nanocrystal including zinc (Zn) and sulfur (S), selenium (Se), tellurium (Te), or a combination thereof; and a shell including a second semiconductor nanocrystal disposed on at least a portion of the core, wherein the core includes a dopant of a Group 1A element, a Group 2A element, or a combination thereof, and the semiconductor nanocrystal particle exhibits a maximum peak emission in a wavelength region of about 440 nanometers (nm) to about 470 nm.

A semiconductor nanocrystal particle including a core including a first semiconductor nanocrystal including zinc (Zn) and sulfur (S), selenium (Se), tellurium (Te), or a combination thereof; and a shell including a second semiconductor nanocrystal disposed on at least a portion of the core, wherein the core includes a dopant of a Group 1A element, a Group 2A element, or a combination thereof, and the semiconductor nanocrystal particle exhibits a maximum peak emission in a wavelength region of about 440 nanometers (nm) to about 470 nm.

A light emitting diode lighting system has a base arranged as a cylinder further comprising a pair of arcuate extensions having a pair of arcuate openings therebetween. Electrical tracks are joined to the base. A semiconductor substrate is arranged around an out surface of the base and connected to the electrical tracks. A polymeric housing is joined to the base and housing the electrical tracks. A germanium layer and a silicon layer are joined to the semiconductor substrate. An outer layer is joined to the germanium layer and the silicon layer and configured to dissipate heat from the germanium layer and the silicon layer. An outer module is joined to the outer layer, and configured to mount the light emitting diode lighting system into an external housing.

A quantum dot including a core that includes a first semiconductor nanocrystal including zinc and selenium, and optionally sulfur and/or tellurium, and a shell that includes a second semiconductor nanocrystal including zinc, and at least one of sulfur or selenium is disclosed. The quantum dot has an average particle diameter of greater than or equal to about 13 nm, an emission peak wavelength in a range of about 440 nm to about 470 nm, and a full width at half maximum (FWHM) of an emission wavelength of less than about 25 nm. A method for preparing the quantum dot, a quantum dot-polymer composite including the quantum dot, and an electronic device including the quantum dot is also disclosed.

Disclosed in an embodiment is a semiconductor device package comprising: a body comprising a cavity; a semiconductor device disposed within the cavity; and a light transmission member disposed on an upper portion of the cavity, wherein the body comprises a first conductive part and a second conductive part disposed to be spaced apart from each other in a first direction, a first insulating part disposed between the first conductive part and the second conductive part, and a second insulating part disclosed in an edge region where a lower surface and side surfaces of the body meet, wherein the cavity comprises a stepped portion on which the light transmission member is disposed, and wherein the second insulating part overlaps with the stepped portion in a vertical direction of the body.