A display apparatus is provided. The display apparatus includes a substrate, a transistor, a metal layer, and a light-emitting diode. The transistor is disposed on the substrate. The metal layer is disposed on the transistor and electrically connected to the transistor, wherein a first distance is between the upper surface of the metal layer and the substrate in a direction perpendicular to the substrate. The light-emitting diode is disposed on the metal layer, wherein the light-emitting diode includes a light-emitting diode body and an electrode, the light-emitting diode body is electrically connected to the metal layer via the electrode, the light-emitting diode body has a first surface and a second surface opposite to the first surface, the first surface and the second surface are parallel to the substrate, and in the direction above, a second distance is between the first surface and the second surface, wherein the ratio of the second distance to the first distance is greater than or equal to 0.25 and less than or equal to 6.

Direct-bonded LED arrays and applications are provided. An example process fabricates a LED structure that includes coplanar electrical contacts for p-type and n-type semiconductors of the LED structure on a flat bonding interface surface of the LED structure. The coplanar electrical contacts of the flat bonding interface surface are direct-bonded to electrical contacts of a driver circuit for the LED structure. In a wafer-level process, micro-LED structures are fabricated on a first wafer, including coplanar electrical contacts for p-type and n-type semiconductors of the LED structures on the flat bonding interface surfaces of the wafer. At least the coplanar electrical contacts of the flat bonding interface are direct-bonded to electrical contacts of CMOS driver circuits on a second wafer. The process provides a transparent and flexible micro-LED array display, with each micro-LED structure having an illumination area approximately the size of a pixel or a smallest controllable element of an image represented on a high-resolution video display.

Described are light emitting diode (LED) devices comprising a plurality of mesas defining pixels, each of the mesas comprising semiconductor layers, an N-contact material in a space between each of the plurality of mesas, a dielectric material which insulates sidewalls of the P-type layer and the active region from the metal. A hard mask layer is above the semiconductor layers, the hard mask layer having a plurality of openings therein, each partially filled with a liner layer and partially filled with a P-metal material plug, the P-metal material plug having a width; and a passivation film is on the hard mask layer, the passivation film having a plurality of passivation film openings therein defining a width, the width of each passivation film opening being less than the width of a combination of the P-metal material plug and the liner layer.

A light-emitting element contains negative ions and positive ions, and includes a solid ionic layer, a layer containing quantum dots, and a cathode electrode and an anode electrode. The ionic layer includes a p-type doped region on the anode electrode side containing the negative ions in a higher quantity than the positive ions, an n-type doped region on the cathode electrode side containing the positive ions in a higher quantity than the negative ions, and a junction region between the p-type doped region and the n-type doped region. The layer containing the quantum dots is adjacent to the junction region. Alternatively, the quantum dots are contained in the junction region. Alternatively, the quantum dots are adjacent to the junction region.

A first pixel configured to emit light of a first color, a second pixel configured to emit light of a second color; and a third pixel configured to emit light of a third color are provided. The first pixel includes a first subpixel and a second subpixel each including a quantum dot light-emitting layer. A light-emission peak wavelength of the second subpixel is longer than a light-emission peak wavelength of the first subpixel.

A display device includes a first electrode, a second electrode disposed spaced apart from the first electrode in a first direction, and an element part disposed between the first electrode and the second electrode. The element part includes light-emitting elements that have a shape extending in one direction and are arranged spaced apart from each other in a second direction perpendicular to the first direction; and a binder surrounding each of the light-emitting elements and fixing the light-emitting elements. The one direction in which the light-emitting elements extend is parallel to the first direction.

A unit pixel of a microdisplay is disclosed. In the unit pixel, sub-pixels that form blue light, green light, and red light are vertically stacked on a growth substrate. Accordingly, the unit pixel area may be reduced, and pixel transfer processing is facilitated.

A display device comprises a signal line on a first surface of a substrate, a lightemitting element on the signal line and comprising a first semiconductor layer, a second semiconductor layer, and an active layer between the first semiconductor layer and the second semiconductor layer, a connection line on a second surface of the substrate and electrically connected to the signal line, and conductive lines on the second surface of the substrate and separated from the connection line. The conductive lines comprise a first conductive layer and a second conductive layer covering the first conductive layer.

A display device includes a substrate including a display area including pixels, a pad area comprising pads and located adjacent to the display area and a side wiring area located adjacent to the pad area; and a printed circuit film attached to the pad area located on a back surface of the first substrate. The plurality of pads include first pads that electrically connect the printed circuit film to the pixels and at least one second pad disposed between adjacent ones of the first pads. The display device further includes at least one connection portion that electrically connects a first pad of the first pads and the at least one second pad to each other. Each of the first pads includes a first-first pad located on a front surface of the first substrate and a first-second pad located on the back surface of the first substrate.

In an LED display device according to an embodiment of the present disclosure, the LED display device comprises a second pixel driving circuit on a substrate, an LED element attached to a region not overlapping the second pixel driving circuit, including a first LED element, a second LED element and a growth substrate, and providing a double light-emitting spectrum, an element fixing layer surrounding the LED element, a first pixel driving circuit on the element fixing layer, and an element protecting layer on the first pixel driving circuit. In addition, the first LED element is controlled by the first pixel driving circuit, and the second LED element is controlled by the second pixel driving circuit. Therefore, the LED display device provides a dual emission spectrum, can realized high luminance and high definition, and can prevent a pixel defect.