Abstract: A light emitting diode (LED) includes quantum dots serving as the quantum well layer in the multiple-quantum well (MQW) structure, which can greatly improve the combination efficiency of electrons and holes due to quantum confinement effect; a nanoscale metal reflective layer is formed between the quantum barrier layer with nanoscale pits to instantly reflect the light emitted downwards from the MQW to the front of epitaxial structure; in addition, the nanoscale metal reflective layer can form surface plasmon to further improve light emitting efficiency.

Abstract: A high-voltage light emitting diode and fabrication method thereof, in which, the liquid insulating material layer/the liquid conducting material layer, after curing, is used for insulating/connecting, making the isolated groove between the light emitting units extremely narrow (opening width?0.4 ?m, such as ?0.3 ?m), which improves single chip output, expands effective light emitting region area and improves light emitting efficiency; the serial/parallel connection yield is improved for this method avoids easy disconnection of wires across a groove with extremely large height difference in conventional high-voltage light emitting diodes; in addition, the manufacturing cost is reduced for the LED can be directly fabricated at the chip fabrication end.

Abstract: A light emitting diode chip includes an epitaxial layer with a plurality of recess portions and protrusion portions over the top layer; a light transmission layer, located between top ends of adjacent protrusion portions and forming holes with the recess portions. The light transmission layer has a horizontal dimension larger than a width of the top ends of two adjacent protrusion portions, and serves as current blocking layer; a current spreading layer covering the surface of the light transmission layer and the surface of an epitaxial layer of a non-mask light transmission layer. As the refractive index of the light transmission layer is between those of the epitaxial layer and the hole, indicating a difference of refractive index between the light transmission layer and the epitaxial layer, the probability of scattering generated when light from a luminescent layer emits upwards can be increased, thus avoiding light absorption by electrodes and improving light extraction efficiency.

Abstract: A flip-chip light LED includes: a substrate; an epitaxial layer on the substrate, wherein, the epitaxial layer comprises: a first semiconductor layer, a second semiconductor layer and a light emitting layer between the first semiconductor layer and the second semiconductor layer; at least one opening structure, which is at the epitaxial layer edge and extends to the substrate surface, making parts of the side wall of the epitaxial layer and the substrate surface exposed, such that the epitaxial layer is divided into an epitaxial bulk layer and a barrier structure; and an insulating layer on the opening structure as the metal electrode isolating layer.

Abstract: A GaN-based LED includes: a substrate with front and back sides; an epitaxial layer formed over the front side of the substrate and including, from top down, a P-type layer, a light-emitting area, and an N-type layer; a current spreading layer formed over the P-type layer; a P electrode formed over the current spreading layer; a first reflecting layer between the current spreading layer and the epitaxial layer, disposed at a peripheral area of the epitaxial layer in a band-shaped distribution; and a second reflecting layer over the back side the substrate. The band-shaped or annular distribution can increase a probability light extraction of the LED sideways. By controlling the ratio of lights extracted upwards and sideways, the light-emitting distribution evenness can be adjusted and the uneven heat dissipation can be improved.

Abstract: A light-emitting diode includes a substrate; a light-emitting epitaxial layer, laminated by semiconductor material layers and formed over the substrate; a first current spreading layer over the light-emitting epitaxial layer; an adhesive layer with alternating second current spreading layers and first metal barrier layers over the first current spreading layer, including three structure layers; a second metal barrier layer over the adhesive layer with alternating second current spreading layers and metal barrier layers; and a metal electrode layer over the second metal barrier layer.

Abstract: A GaN-based LED with a current spreading structure, the LED including a substrate, a light-emitting epitaxial layer over the substrate, and a current spreading structure over the light-emitting epitaxial layer. The current spreading structure includes a transparent electrode spreading bar, and a metal electrode spreading bar attached to the side wall of the transparent electrode spreading bar. The current spreading structure can improve the current spreading effect, reducing or eliminating of electrode shading, improving luminous efficiency of the LED, and avoid or reduce high voltage (Vf).

Abstract: A light emitting diode includes: a substrate; a light-emitting epitaxial layer, from bottom to up, laminated by semiconductor material layers of a first confinement layer, a light-emitting layer and a second confinement layer over the substrate; a current blocking layer over partial region of the light-emitting epitaxial layer; a transparent conducting structure over the current blocking layer that extends to the light-emitting epitaxial layer surface and is divided into a light-emitting region and a non-light-emitting region, in which, the non-light-emitting region corresponds to the current blocking layer with thickness larger than that of the light-emitting region, thus forming a good ohmic contact between this structure and the light-emitting epitaxial layer and reducing light absorption; and a P electrode over the non-light-emitting region of the transparent conducting structure, which guarantees current spreading performance and reduces working voltage and light absorption.

Abstract: A GaN-based LED includes a substrate; an epitaxial layer over the substrate; a current spreading layer over a P-type layer; and a P electrode over the current spreading layer. The epitaxial layer includes the P-type layer, a light-emitting area, and an N-type layer. An annular reflecting layer and a metal reflecting layer are formed between the P electrode and the epitaxial layer. The geometric center vertically corresponds to the P electrode; the annular reflecting layer is formed between the current spreading layer and the P-type layer; the metal reflecting layer is formed between the current spreading layer and the P electrode; and a preset distance is arranged between the annular reflecting layer and the metal reflecting layer. The annular reflecting layer and the metal reflecting layer reduce light absorption of the P electrode and improve light extraction efficiency.

Abstract: A light emitting diode includes: a substrate; a light-emitting epitaxial layer, from bottom to up, laminated by semiconductor material layers of a first confinement layer, a light-emitting layer and a second confinement layer over the substrate; a current blocking layer over partial region of the light-emitting epitaxial layer; a transparent conducting structure over the current blocking layer that extends to the light-emitting epitaxial layer surface and is divided into a light-emitting region and a non-light-emitting region, in which, the non-light-emitting region corresponds to the current blocking layer with thickness larger than that of the light-emitting region, thus forming a good ohmic contact between this structure and the light-emitting epitaxial layer and reducing light absorption; and a P electrode over the non-light-emitting region of the transparent conducting structure, which guarantees current spreading performance and reduces working voltage and light absorption.

Abstract: A GaN-based LED with a current spreading structure, the LED including a substrate, a light-emitting epitaxial layer over the substrate, and a current spreading structure over the light-emitting epitaxial layer. The current spreading structure includes a transparent electrode spreading bar, and a metal electrode spreading bar attached to the side wall of the transparent electrode spreading bar. The current spreading structure can improve the current spreading effect, reducing or eliminating of electrode shading, improving luminous efficiency of the LED, and avoid or reduce high voltage (Vf).

Abstract: A light-emitting diode includes a substrate; a light-emitting epitaxial layer, laminated by semiconductor material layers and formed over the substrate; a first current spreading layer over the light-emitting epitaxial layer; an adhesive layer with alternating second current spreading layers and first metal barrier layers over the first current spreading layer, including three structure layers; a second metal barrier layer over the adhesive layer with alternating second current spreading layers and metal barrier layers; and a metal electrode layer over the second metal barrier layer.

Abstract: A GaN-based LED includes: a substrate with front and back sides; an epitaxial layer formed over the front side of the substrate and including, from top down, a P-type layer, a light-emitting area, and an N-type layer; a current spreading layer formed over the P-type layer; a P electrode formed over the current spreading layer; a first reflecting layer between the current spreading layer and the epitaxial layer, disposed at a peripheral area of the epitaxial layer in a band-shaped distribution; and a second reflecting layer over the back side the substrate. The band-shaped or annular distribution can increase a probability light extraction of the LED sideways. By controlling the ratio of lights extracted upwards and sideways, the light-emitting distribution evenness can be adjusted and the uneven heat dissipation can be improved.

Abstract: A GaN-based LED includes a substrate; an epitaxial layer over the substrate; a current spreading layer over a P-type layer; and a P electrode over the current spreading layer. The epitaxial layer includes the P-type layer, a light-emitting area, and an N-type layer. An annular reflecting layer and a metal reflecting layer are formed between the P electrode and the epitaxial layer. The geometric center vertically corresponds to the P electrode; the annular reflecting layer is formed between the current spreading layer and the P-type layer; the metal reflecting layer is formed between the current spreading layer and the P electrode; and a preset distance is arranged between the annular reflecting layer and the metal reflecting layer. The annular reflecting layer and the metal reflecting layer reduce light absorption of the P electrode and improve light extraction efficiency.

Abstract: The present invention discloses a method for lift-off of an LED substrate. By eroding the sidewall of a GaN epitaxial layer, cavity structures are formed, which may act in cooperation with a non-fully filled patterned sapphire substrate from epitaxial growth to cause the GaN epitaxial layer to separate from the sapphire substrate. The method according to an embodiment of the present invention can effectively reduce the dislocation density in the growth of a GaN-based epitaxial layer; improve lattice quality, and realize rapid lift-off of an LED substrate, and has the advantages including low cost, no internal damage to the GaN film, elevated performance of the photoelectric device and improved luminous efficiency.

Abstract: The invention discloses an AlGaInP-based LED with double reflective layers and a fabrication method thereof. The method includes: providing a temporary substrate; forming an epitaxial layer on a front of the temporary substrate; forming a distributed Bragg reflector on the epitaxial layer; forming an some openings in the distributed Bragg reflector, such that the arrangement of the distributed Bragg reflector is grid-like and a portion of a top of the epitaxial layer is exposed; forming a reflective metal layer on the distributed Bragg reflector and on the exposed portion of the top of the epitaxial layer, to fill the openings; bonding a permanent substrate onto the reflective metal layer; removing the temporary substrate; forming a first electrode and a second electrode at a bottom of the epitaxial layer and a top of the permanent substrate, respectively; and dicing to obtain the AlGaInP-based LED chips.

Abstract: The present invention discloses a method for lift-off of an LED substrate. By eroding the sidewall of a GaN epitaxial layer, cavity structures are formed, which may act in cooperation with a non-fully filled patterned sapphire substrate from epitaxial growth to cause the GaN epitaxial layer to separate from the sapphire substrate. The method according to an embodiment of the present invention can effectively reduce the dislocation density in the growth of a GaN-based epitaxial layer; improve lattice quality, and realize rapid lift-off of an LED substrate, and has the advantages including low cost, no internal damage to the GaN film, elevated performance of the photoelectric device and improved luminous efficiency.

Abstract: The present invention discloses a double-reflective-layer gallium nitride-based flip-chip light-emitting diode with both a distributed Bragg reflector and a metal reflective layer on its side and a fabrication method thereof. The light-emitting diode includes: a sapphire substrate; a buffer layer, an N-GaN layer, a multiple-quantum-well layer and a P-GaN layer stacked on the sapphire substrate in that order; a transparent conductive layer formed on the P-GaN layer; a distributed Bragg reflector formed over a side of the epitaxial layer and the transparent conductive layer; a metal reflective layer formed on the DBR; a P-type ohmic contact electrode formed on the transparent conductive layer; and an N-type ohmic contact electrode formed on the exposed N-GaN layer, wherein the P-type ohmic contact electrode and the N-type ohmic contact electrode are bonded to a heat dissipation substrate through a metal conductive layer and a ball bonder.

Abstract: The invention discloses an AlGaInP-based LED with double reflective layers and a fabrication method thereof. The method includes: providing a temporary substrate; forming an epitaxial layer on a front of the temporary substrate; forming a distributed Bragg reflector on the epitaxial layer; forming an some openings in the distributed Bragg reflector, such that the arrangement of the distributed Bragg reflector is grid-like and a portion of a top of the epitaxial layer is exposed; forming a reflective metal layer on the distributed Bragg reflector and on the exposed portion of the top of the epitaxial layer, to fill the openings; bonding a permanent substrate onto the reflective metal layer; removing the temporary substrate; forming a first electrode and a second electrode at a bottom of the epitaxial layer and a top of the permanent substrate, respectively; and dicing to obtain the AlGaInP-based LED chips.