The present invention discloses a bidirectional ultraviolet light emitting diode (UV LED) based on N—ZnO/N—GaN/N—ZnO heterojunction as well as its preparation method. The LED includes: N—ZnO microwires, a N—GaN film, a PMMA protective layer and alloy electrodes; and its preparation method includes the following steps: lay two N—ZnO microwires on the N—GaN film, then spin-coat a PMMA protective layer on the film to fix the N—ZnO microwires until the PMMA protective layer spreads over the N—ZnO microwires, and then place the film on a drying table to solidify the PMMA protective layer; then etch the PMMA protective layer with O.sub.2 to expose the N—ZnO microwires, and prepare alloy electrodes on different N—ZnO microwires to construct a N—ZnO/N—GaN/N—ZnO heterojunction to constitute a complete device. The present invention constructs an N/N/N symmetrical structure; the device is composed of N—ZnO and N—GaN, emits light in the ultraviolet region and has a small turn-on voltage.

Various forms of Mg.sub.xGe.sub.1-xO.sub.2-x are disclosed, where the Mg.sub.xGe.sub.1-xO.sub.2-x are epitaxial layers formed on a substrate comprising a substantially single crystal substrate material. The epitaxial layer of Mg.sub.xGe.sub.1-xO.sub.2-x has a crystal symmetry compatible with the substrate material. Semiconductor structures and devices comprising the epitaxial layer of Mg.sub.xGe.sub.1-xO.sub.2-x are disclosed, along with methods of making the epitaxial layers and semiconductor structures and devices.

Light-emitting devices and displays with improved performance are disclosed. A light-emitting device includes an emissive material disposed between a first electrode, and a second electrode. Various embodiments include a device having a peak external quantum efficiency of at least about 2.2%; a device that emits light having a CIE color coordinate of x greater than 0.63; a device having an external quantum efficiency of at least about 2.2 percent when measured at a current density of 5 mA/cm.sup.2. Also disclosed is a light-emitting device comprising a plurality of semiconductor nanocrystals capable of emitting red light upon excitation, wherein the device has a peak luminescent efficiency of at least about 1.5 lumens per watt. Also disclosed is a light-emitting device comprising a plurality of semiconductor nanocrystals capable of emitting red light upon excitation, wherein the device has a luminescent efficiency of at least about 1.5 lumens per watt when measured at a current density of 5 milliamps/square centimeter. Also disclosed is a light-emitting device comprising a plurality of semiconductor nanocrystals capable of emitting green light upon excitation, wherein the device has a peak external quantum efficiency of at least about 1.1 percent. Further disclosed is a light-emitting device comprising a plurality of semiconductor nanocrystals, wherein the device has a luminescent efficiency of at least about 3 lumens per watt when measured at a current density of 5 mA/cm.sup.2. Further disclosed is a light-emitting device comprising a plurality of semiconductor nanocrystals capable of emitting green light upon excitation, wherein the device has an external quantum efficiency of at least about 2% when measured at a current density of 5 mA/cm.sup.2. Other light-emitting devices and displays with improved performance are disclosed. Also disclosed are methods for preparing and for purifying semiconductor nanocrystals.

A nanostructured hybrid particle, a manufacturing method thereof, and a device including the nanostructured hybrid particle are disclosed. The nanostructured hybrid particle includes a hydrophobic base particle having a convex-concave nanopattern on a surface thereof; a hydrophobic light-emitting nanoparticle disposed in a concave portion of the convex-concave nanopattern on the surface of hydrophobic base particle; and a coating layer covering the hydrophobic base particle and the hydrophobic light-emitting nanoparticle. In the nanostructured hybrid particle, light extraction may occur in all 3-dimensional directions, and thus, the nanostructured hybrid particle can exhibit high light extraction efficiency compared to light extraction occurring on a two-dimensional plane.

Disclosed is a multi-color semiconductor LED display with integrated with CMOS circuit components, such as thin film transistors (TFTs). LEDs of the display are disposed on a first major surface of a substrate while CMOS circuit components which are configured as circuitry for operating the display are disposed on a second opposing major surface of the substrate. The CMOS components and LEDs are coupled by through silicon via (TSV) contacts through the substrate. Integrating CMOS components with LED on one substrate enhances compactness of the display. Other advantages include low power and low cost with high brightness and resolution desired for portable applications, including virtual reality and augmented reality applications.

An array substrate, a liquid crystal display panel and a display device with a simple structure are provided. The array substrate includes: a substrate; a plurality of sub-pixel units, located on the substrate and arranged in a matrix form; and a plurality of photoluminescent devices, located in the plurality of sub-pixel units, and emitting light with a corresponding color in correspondence with a color of the sub-pixel unit where it is located.

The present invention discloses a bidirectional ultraviolet light emitting diode (UV LED) based on N—ZnO/N—GaN/N—ZnO heterojunction as well as its preparation method. The LED includes: N—ZnO microwires, a N—GaN film, a PMMA protective layer and alloy electrodes; and its preparation method includes the following steps: lay two N—ZnO microwires on the N—GaN film, then spin-coat a PMMA protective layer on the film to fix the N—ZnO microwires until the PMMA protective layer spreads over the N—ZnO microwires, and then place the film on a drying table to solidify the PMMA protective layer; then etch the PMMA protective layer with O.sub.2 to expose the N—ZnO microwires, and prepare alloy electrodes on different N—ZnO microwires to construct a N—ZnO/N—GaN/N—ZnO heterojunction to constitute a complete device. The present invention constructs an N/N/N symmetrical structure; the device is composed of N—ZnO and N—GaN, emits light in the ultraviolet region and has a small turn-on voltage.

Various forms of Mg.sub.xGe.sub.1-xO.sub.2-x are disclosed, where the MgxGe.sub.1-xO.sub.2-x are epitaxial layers formed on a substrate comprising a substantially single crystal substrate material. The epitaxial layer of Mg.sub.xGe.sub.1-xO.sub.2-x has a crystal symmetry compatible with the substrate material. Semiconductor structures and devices comprising the epitaxial layer of Mg.sub.xGe.sub.1-xO.sub.2-x are disclosed, along with methods of making the epitaxial layers and semiconductor structures and devices.

Various forms of Mg.sub.xGe.sub.1-xO.sub.2-x are disclosed, where the Mg.sub.xGe.sub.1-xO.sub.2-x are epitaxial layers formed on a substrate comprising a substantially single crystal substrate material. The epitaxial layer of Mg.sub.xGe.sub.1-xO.sub.2-x has a crystal symmetry compatible with the substrate material. Semiconductor structures and devices comprising the epitaxial layer of Mg.sub.xGe.sub.1-xO.sub.2-x are disclosed, along with methods of making the epitaxial layers and semiconductor structures and devices.

A unipolar-doped light emitting diode or laser diode is described. The diode includes a bottom region having an n-type layer, a top region having an n-type layer, and a middle region between the top and bottom regions having at least one material different from the top or bottom region forming two or more heterojunctions. The top and bottom regions create light emission by interband tunneling-induced photon emission. Systems including the unipolar-doped diode including LIDAR are also taught.