A micro semiconductor structure is provided. The micro semiconductor structure includes a substrate, at least one supporting layer, and at least one micro semiconductor device. The supporting layer includes at least one upper portion and a bottom portion, wherein the upper portion extends in a first direction. The length L1 of the upper portion in the first direction is greater than the length L2 of the bottom portion in the first direction. Furthermore, the bottom surface of the micro semiconductor device is in direct contact with the upper portion of the supporting layer.

A micro semiconductor structure is provided. The micro semiconductor structure includes a substrate, at least one supporting layer, and at least one micro semiconductor device. The supporting layer includes at least one upper portion and a bottom portion, wherein the upper portion extends in a first direction. The length L1 of the upper portion in the first direction is greater than the length L2 of the bottom portion in the first direction. Furthermore, the bottom surface of the micro semiconductor device is in direct contact with the upper portion of the supporting layer.

An optical semiconductor device includes: a mesa that is provided on a surface in a <011> direction of a semiconductor substrate having a (100) plane orientation and being of a first conductivity type, and includes a first cladding layer of the first conductivity type, an active layer, and a second cladding layer of a second conductivity type; a semi-insulating buried layer that buries both sides of the mesa, is provided on the semiconductor substrate, and includes a first region and a second region farther from the mesa than the first region; an insulation film provided on the first and second regions of the buried layer; and an electrode provided on the mesa and the insulation film on the first region; wherein a surface of the first region is at a height equal to or lower than a surface of the mesa, and lowers at farther distances from the mesa.

An optical semiconductor device includes: a mesa that is provided on a surface in a <011> direction of a semiconductor substrate having a (100) plane orientation and being of a first conductivity type, and includes a first cladding layer of the first conductivity type, an active layer, and a second cladding layer of a second conductivity type; a semi-insulating buried layer that buries both sides of the mesa, is provided on the semiconductor substrate, and includes a first region and a second region farther from the mesa than the first region; an insulation film provided on the first and second regions of the buried layer; and an electrode provided on the mesa and the insulation film on the first region; wherein a surface of the first region is at a height equal to or lower than a surface of the mesa, and lowers at farther distances from the mesa.

A light string includes an illumination device, a first wire, a second wire, soldering material, and transparent adhesive. The illumination device includes two soldering portions. The conductors of the first wire and the second wire are partially exposed to form a first soldering section and a second soldering section. Soldering material is used to attach the first soldering section and the second soldering section to the two soldering portions. The transparent adhesive forms a layer over, and covers, the illumination device, the first soldering section and the second soldering section, and extends to partially cover other portions of the first wire and the second wire.

A light string includes an illumination device, a first wire, a second wire, soldering material, and transparent adhesive. The illumination device includes two soldering portions. The conductors of the first wire and the second wire are partially exposed to form a first soldering section and a second soldering section. Soldering material is used to attach the first soldering section and the second soldering section to the two soldering portions. The transparent adhesive forms a layer over, and covers, the illumination device, the first soldering section and the second soldering section, and extends to partially cover other portions of the first wire and the second wire.

A light-emitting device including an epitaxial layer, a support layer, an insulating layer, a first electrode pad, and a second electrode pad is provided. The epitaxial layer includes a first type doped semiconductor layer, a light-emitting layer and a second type doped semiconductor layer, wherein the light-emitting layer is disposed on a partial area of the first type doped semiconductor layer and is between the first type doped semiconductor layer and the second type doped semiconductor layer. The support layer covers the second type doped semiconductor layer while the insulating layer covers the epitaxial layer and the support layer. The first and the second electrode pads are disposed over the insulating layer and electrically connected to the first and the second type doped semiconductor layers, respectively. The support layer extends from a first position below the first electrode pad to a second position below the second electrode pad.

The disclosed technology provides micro-assembled micro-LED displays and lighting elements using arrays of micro-LEDs that are too small (e.g., micro-LEDs with a width or diameter of 10 m to 50 m), numerous, or fragile to assemble by conventional means. The disclosed technology provides for micro-LED displays and lighting elements assembled using micro-transfer printing technology. The micro-LEDs can be prepared on a native substrate and printed to a display substrate (e.g., plastic, metal, glass, or other materials), thereby obviating the manufacture of the micro-LEDs on the display substrate. In certain embodiments, the display substrate is transparent and/or flexible.

The disclosed technology provides micro-assembled micro-LED displays and lighting elements using arrays of micro-LEDs that are too small (e.g., micro-LEDs with a width or diameter of 10 m to 50 m), numerous, or fragile to assemble by conventional means. The disclosed technology provides for micro-LED displays and lighting elements assembled using micro-transfer printing technology. The micro-LEDs can be prepared on a native substrate and printed to a display substrate (e.g., plastic, metal, glass, or other materials), thereby obviating the manufacture of the micro-LEDs on the display substrate. In certain embodiments, the display substrate is transparent and/or flexible.

Disclosed in an embodiment is a semiconductor device comprising: a semiconductor structure comprising a first conductive type semiconductor layer, a second conductive type semiconductor layer, and an active layer disposed between the first conductive type semiconductor layer and the second conductive type semiconductor layer; a second electrode electrically connected to the second conductive type semiconductor layer; and a reflective layer disposed under the second electrode, wherein the second conductive type semiconductor layer comprises a first sub-layer and a second sub-layer disposed between the first sub-layer and the active layer and having an aluminum (Al) composition higher than that of the first sub-layer, the reflective layer comes into contact with the lower surface of the second sub-layer, and the second electrode comes into contact with the first sub-layer.