A red light-emitting element includes an anode, a cathode, and a red light-emitting layer, the red light-emitting layer includes a compound including Sn (IV) and a chalcogen, a quantum dot, a first compound including Sn (II) and a chalcogen of the same element as the chalcogen, and a chalcogenium ion of the same element as the chalcogen, and a substance amount rate of Sn (II) to Sn (IV) is more than 0% and equal to or less than 50%.

A quantum dot material includes a quantum dot body and a ligand material coordinately bonded to the quantum dot body. The quantum dot material further includes a cross-linking agent, and the cross-linking agent includes at least two diazonaphthoquinone units. Each of the at least two diazonaphthoquinone units is configured to undergo a photochemical reaction under irradiation to generate a carbene intermediate; the ligand material is configured to be bonded to the carbene intermediate through an addition reaction to form a cross-linked quantum dot material.

A light-emitting diode epitaxial structure and a method for forming the same are provided. The light-emitting diode epitaxial structure includes: an N-type semiconductor structure, a quantum well light-emitting layer and a P-type semiconductor structure which are stacked. The quantum well light-emitting layer is disposed between the N-type semiconductor structure and the P-type semiconductor structure. The P-type semiconductor structure includes a P-type current spreading layer and a P-type confinement layer, and the P-type confinement layer is disposed between the quantum well light-emitting layer and the P-type current spreading layer. A material of the P-type current spreading layer has a first lattice constant, a material of the P-type confinement layer has a second lattice constant, and a mismatch between the first lattice constant and the second lattice constant is less than or equal to 1%.

In an embodiment an optoelectronic device includes an epitaxially grown functional layer stack having a first layer, an active region arranged on the first layer, a second layer arranged on the active region and a third layer arranged on the second layer, the third layer having a higher concentration of the dopant of the second conductivity type than the second layer and an electrically conductive contact layer arranged on the third layer, wherein the functional layer stack is laterally limited by side surfaces of the functional layer stack and includes a central region along a center line of the functional layer stack, wherein the central region is spaced from the side surfaces, wherein a current path from the electrically conductive contact layer through the third layer to the second layer is limited to the central region, and wherein the third layer includes at least one intersection and the at least one intersection divides the third layer into at least a first region and a second region separated from the first region, the first region being limited to the central region.

A method of manufacturing a light-emitting diode device comprises fabricating a light-emitting diode structure comprising an inorganic semiconductor; and fabricating an optic over the light-emitting diode structure using nano-imprint lithography. The method may further comprise, before fabricating the optic, forming a first lens on the light-emitting diode structure by thermal reflow lithography. The optic and first lens may improve the efficiency of the light-emitting diode device by reducing losses due to total internal reflection. Also provided are light emitting diode devices obtainable by the method.

A photo coupler single chip structure and a manufacturing method thereof are provided. The photo coupler single chip structure includes a light-emitting unit, a light-receiving unit and an electrical insulation layer. The electrical insulation layer physically connects the light-emitting unit and the light-receiving unit to two opposite sides of the electrical insulation layer. The light-emitting unit can form an optical signal in response to an input signal. The light-receiving unit will directly absorb the optical signal through the electrical insulating layer and convert it into an output signal.

A micro light emitting device includes a first semiconductor layer doped with a first conductivity type, a light emitting layer arranged on an upper surface of the first semiconductor layer, a second semiconductor layer arranged on an upper surface of the light emitting layer and doped with a second conductivity type electrically opposite to the first conductivity type, an insulating layer arranged on an upper surface of the second semiconductor layer, a first electrode arranged on an upper surface of the insulating layer and electrically connected to the first semiconductor layer, a second electrode arranged on the upper surface of the insulating layer and electrically connected to the second semiconductor layer, and an aluminum nitride layer arranged on a lower surface of the first semiconductor layer and having a flat surface.

Micro-LED structures include an LED epilayer that may be formed before the micro-LED structure is coupled to a backplane substrate. In order to prevent light leakage and maximize light output, the sidewalls and other surfaces of the LED epilayer may be coated with a reflective coating. For example, the reflective coating may include a metal layer that is electrically insulated between dielectric layers from the micro-LED electrodes. The reflective coating may also be formed using multiple layers in a distributed Bragg reflector configuration. This reflective coating may be formed during the LED fabrication process before the micro-LED structure is coupled to the backplane. The pixel isolation structures on the backplane may also include a reflective coating that is applied above the LED epilayers.