Abstract: A micro light-emitting diode (LED) includes an n-type layer, a transitional unit, a light-emitting unit disposed on the transitional unit, and a p-type layer disposed on the light-emitting unit. The transitional unit includes a first transitional layer, a second transitional layer and a third transitional layer that are sequentially disposed on the n-type layer in such order. The n-type layer, the first transitional layer, the second transitional layer, the third transitional layer and the light-emitting unit respectively have a bandgap of Egn, a bandgap of Eg1, a bandgap of Eg2, a bandgap of Eg3 and a bandgap of Ega which satisfy a relationship of Egn?Eg1>Eg2>Eg3>Ega.

Abstract: A light-emitting structure includes an n-type layer, an active layer, and a p-type layer. The active layer has N quantum well structure periods, each of the N quantum-well structure periods has a well layer and at least one barrier layer. The N quantum-well structure periods include a first light-emitting section and a second light-emitting section. The first light-emitting section is closer to the n-type layer than the second light-emitting section. A method for producing the light-emitting structure, and a light-emitting device that has the light-emitting structure are also disclosed.

Abstract: A light-emitting diode (LED) includes a substrate, an epitaxial layered structure, and a strain tuning layer. The epitaxial layered structure includes a buffer layer, an N-type cladding layer, an active layer, and a P-type cladding layer formed on the substrate in such order. The active layer includes a multiple quantum well structure. The strain tuning layer is disposed between the N-type cladding layer and the active layer, and has a lattice constant that is smaller than that of the N-type cladding layer. A method for manufacturing the LED is also disclosed.

Abstract: A nitride based semiconductor device including a buffer layer, a three-dimensional stress tuning layer formed on the buffer layer, a first-type semiconductor layer formed on the three-dimensional stress tuning layer, an active layer formed on the first-type semiconductor layer, and a second-type semiconductor layer formed on the active layer. The three-dimensional stress tuning layer and the buffer layer cooperatively define an interface therebetween. The interface has a three-dimensional composition distribution.

Abstract: A semiconductor device includes a substrate, a stress tuning layer disposed on the substrate, an aluminum nitride (AlN) buffer layer disposed on the stress tuning layer, an n-type semiconductor layer disposed on the AlN buffer layer, an active layer disposed on the n-type semiconductor layer, and a p-type semiconductor layer disposed on the active layer. The stress tuning layer has a lattice constant larger than that of the AlN buffer layer and no larger than that of the n-type semiconductor layer. A method of manufacturing the semiconductor device is also provided.

Abstract: A fabrication method of a nitride underlayer structure includes, during AlN layer sputtering with PVD, a small amount of non-Al material is doped to form nitride with decomposition temperature lower than that of AlN. A high-temperature annealing is then performed. After annealing, the AlN layer has a rough surface with microscopic ups and downs instead of a flat surface. By continuing AlGaN growth via MOCVD over this surface, the stress can be released via 3D-2D mode conversion, thus improving AlN cracks.

Abstract: A nitride based semiconductor device including a buffer layer, a three-dimensional stress tuning layer formed on the buffer layer, a first-type semiconductor layer formed on the three-dimensional stress tuning layer, an active layer formed on the first-type semiconductor layer, and a second-type semiconductor layer formed on the active layer. The three-dimensional stress tuning layer and the buffer layer cooperatively define an interface therebetween. The interface has a three-dimensional composition distribution.

Abstract: A fabrication method of a nitride underlayer structure includes, during AlN layer sputtering with PVD, a small amount of non-Al material is doped to form nitride with decomposition temperature lower than that of AlN. A high-temperature annealing is then performed. After annealing, the AlN layer has a rough surface with microscopic ups and downs instead of a flat surface. By continuing AlGaN growth via MOCVD over this surface, the stress can be released via 3D-2D mode conversion, thus improving AlN cracks.

Abstract: A nitride light emitting diode includes: an n-type nitride layer, a light emitting layer and a p-type nitride layer in sequence, wherein, the light emitting layer is a MQW structure composed of a barrier layer and a well layer, in which, an AlGaN electron tunneling layer is inserted into at least one well layer closing to the n-type nitride layer with barrier height greater than that of the barrier layer; in addition, the barriers of the AlGaN electron tunneling layer and the well layer are high enough so that electrons are difficult to transit towards thermionic emission direction, but mainly transit through tunneling in the InGaN well layers, which confines electron mobility and adjusts electron distribution. Hence, electrons have less chance to spill over into the P-type nitride layer.

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.