Provided are nanorod light emitting diodes (LEDs), display apparatuses, and manufacturing methods thereof. The nanorod LED includes a first-type semiconductor layer including a body and a pyramidal structure continuously provided from the body, a nitride light emitting layer provided on the pyramidal structure, and a second-type semiconductor layer provided in the nitride light emitting layer.

GaN-based nanowire heterostructures have been intensively studied for applications in light emitting diodes (LEDs), lasers, solar cells and solar fuel devices. Surface charge properties play a dominant role on the device performance and have been addressed within the prior art by use of a relatively thick large bandgap AlGaN shell covering the surfaces of axial InGaN nanowire LED heterostructures has been explored and shown substantial promise in reducing surface recombination leading to improved carrier injection efficiency and output power. However, these lead to increased complexity in device design, growth and fabrication processes thereby reducing yield/performance and increasing costs for devices. Accordingly, there are taught self-organising InGaN/AlGaN core-shell quaternary nanowire heterostructures wherein the In-rich core and Al-rich shell spontaneously form during the growth process.

GaN-based nanowire heterostructures have been intensively studied for applications in light emitting diodes (LEDs), lasers, solar cells and solar fuel devices. Surface charge properties play a dominant role on the device performance and have been addressed within the prior art by use of a relatively thick large bandgap AlGaN shell covering the surfaces of axial InGaN nanowire LED heterostructures has been explored and shown substantial promise in reducing surface recombination leading to improved carrier injection efficiency and output power. However, these lead to increased complexity in device design, growth and fabrication processes thereby reducing yield/performance and increasing costs for devices. Accordingly, there are taught self-organising InGaN/AlGaN core-shell quaternary nanowire heterostructures wherein the In-rich core and Al-rich shell spontaneously form during the growth process.

The techniques described herein relate to a transistor including a substrate including sapphire, an epitaxial channel layer on the substrate, and an epitaxial gate layer on the channel layer. The epitaxial channel layer can include -Ga.sub.2O.sub.3, with a first bandgap. The epitaxial gate layer can include an oxide material with a second bandgap, wherein the second bandgap is wider than the first bandgap. The transistor can also include electrical contacts, including: a source electrical contact coupled to the epitaxial channel layer; a drain electrical contact coupled to the epitaxial channel layer; and a gate electrical contact coupled to the epitaxial gate layer.

The techniques described herein relate to a transistor including a substrate including sapphire, an epitaxial channel layer on the substrate, and an epitaxial gate layer on the channel layer. The epitaxial channel layer can include -Ga.sub.2O.sub.3, with a first bandgap. The epitaxial gate layer can include an oxide material with a second bandgap, wherein the second bandgap is wider than the first bandgap. The transistor can also include electrical contacts, including: a source electrical contact coupled to the epitaxial channel layer; a drain electrical contact coupled to the epitaxial channel layer; and a gate electrical contact coupled to the epitaxial gate layer.

A method of manufacturing a semiconductor light emitting element includes: providing a first light emitting part that includes a first active layer, providing a first semiconductor layer, forming a first bonding face that extends in a first crystal plane, which includes either one of (i) subjecting a principal face of the first light emitting part to an acidic or alkaline solution treatment, or (ii) polishing the principal face of the first light emitting part, forming a second bonding face that extends in a second crystal plane having a plane orientation different from a plane orientation of the first crystal plane, which includes the other one of (i) subjecting a principal face of the first semiconductor layer to an acidic or alkaline solution treatment, or (ii) polishing the principal face of the first semiconductor layer, and directly bonding the first bonding face and the second bonding face.

A micro light-emitting device display apparatus includes a plurality of micro light-emitting devices. Each micro light-emitting device includes a first light-emitting layer including a first epitaxial structure configured to emit light of a first wavelength and a second light-emitting layer bonded and stacked onto the first light-emitting layer through a metal layer, and including a second epitaxial structure configured to emit light of a second wavelength and a third epitaxial structure configured to emit light of a third wavelength. The second epitaxial structure and the third epitaxial structure are nanorod arrays of a same epitaxial material. The third wavelength is greater than the second wavelength. Both the second wavelength and the third wavelength are less than the first wavelength. A sum of orthographic projection areas of the second epitaxial structure and the third epitaxial structure is less than an orthographic projection area of the first epitaxial structure.

A quantum dot includes: a core including a first semiconductor nanocrystal, and a shell disposed on the core, the shell including a second semiconductor nanocrystal and a dopant, wherein the first semiconductor nanocrystal includes a Group III-V compound, the second semiconductor nanocrystal includes zinc (Zn), sulfur (S), and selenium, and the dopant includes lithium, a Group 2A metal having an effective ionic radius less than an effective ionic radius of Zn.sup.2+, a Group 3A element having an effective ionic radius less than an effective ionic radius of Zn.sup.2+, or a combination thereof. Also a method of producing the quantum dot, and a composite, and an electronic device including the quantum dot.

A quantum dot includes: a core including a first semiconductor nanocrystal, and a shell disposed on the core, the shell including a second semiconductor nanocrystal and a dopant, wherein the first semiconductor nanocrystal includes a Group III-V compound, the second semiconductor nanocrystal includes zinc (Zn), sulfur (S), and selenium, and the dopant includes lithium, a Group 2A metal having an effective ionic radius less than an effective ionic radius of Zn.sup.2+, a Group 3A element having an effective ionic radius less than an effective ionic radius of Zn.sup.2+, or a combination thereof. Also a method of producing the quantum dot, and a composite, and an electronic device including the quantum dot.

A method of forming a dielectric collar for semiconductor wires includes providing a layers stack and a semiconductor wires (SW) layer on top of the stack, forming a base layer at a lower part of the SW and a capping layer at an upper part of the SW, the base layer parallel to the basal plane and including a dielectric material surrounding the lower part of the SW, and the capping layer along a contour of the SW and including a dielectric material surrounding the upper part of the SW, the base and capping layers having thicknesses e1 and e2 with e1>2.e2, performing anisotropic etching along the direction normal to the basal plane to remove the dielectric material at a top part of the SW and leaving the dielectric material at least in the lower part of the SW.