摘要:
A light emitting diode includes a first conductivity type GaAs substrate having a second conductivity type region as a current blocking layer. A first conductivity type distributed Bragg reflector layer is formed on the GaAs substrate. An AlGaInP double heterostructure including a lower cladding AlGaInP layer of the first conductivity type, an undoped active AlGaInP layer, and an upper cladding AlGaInP layer of the second conductivity type is grown on top of the distributed Bragg reflector layer. The undoped active AlGaInP layer can also be replaced by a multi-layer quantum well structure of AlGaInP or a strained multi-layer quantum well structure of AlGaInP. A second conductivity type layer of low energy band gap and high conductivity material is formed on the AlGaInP double heterostructure. A GaP window layer of the second conductivity type is then formed on top of the low energy band gap layer.
摘要:
A light emitting diode comprises a multiple quantum well structure. The light emitting diode has a first conductivity type GaAs substrate, an AlGaInP lower cladding layer of the first conductivity type, a multiple quantum well structure, an AlGaInP upper cladding layer of a second conductivity type, and a window structure of the second conductivity type. The multiple quantum well structure comprises a plurality of AlGaInP quantum well layers and barrier layers being stacked alternatively on each other. The window structure including a thin layer having low energy band gap and high conductivity GaAs or GaInP, and a thicker layer having high energy band gap and transparent GaP containing a small amount of In. The use of multiple quantum well structure improves the light intensity and the Iv-I curve linearity of the light emitting diode. The small amount of In in the window layer reduces the defect density generated in the GaP layer due to the lattice mismatch between the window layer and the upper cladding layer. Another improvement that includes growing a distributed Bragg reflector layer between the lower cladding layer and substrate is also presented to further increase the luminous efficiency of the light emitting diode.
摘要:
The present invention is to provide a semiconductor device which includes a mounting base and a light-emitting device. The mounting base includes a substrate of a first semiconductor material and a first layer of a material with high thermal conductivity formed over the substrate. Furthermore, the light-emitting device is a multi-layer structure which includes at least a second layer of a second semiconductor material. The light-emitting device is mounted on the first layer of the mounting base. Moreover, the difference of the thermal expansion coefficient between the first semiconductor material and the second semiconductor material is between a predetermined range.
摘要:
A suction-type transmission apparatus includes at least one suction region allocation member and a suction wheel member. The suction region allocation member has a chamber and through holes communicating with the chamber. The suction wheel member is pivoted to the suction region allocation member, and includes an inner lining body with gas flow channels disposed in parallel, and an outer ring sleeve. The inner lining body has gas holes corresponding to the through holes and being in communication with the gas flow channels. The outer ring sleeve with micro-pores in communication with the gas flow channels is sleeved on the inner lining body, and wraps the gas flow channels. The chamber is connected to a gas extraction port, and at least one sealing element is selectively disposed in the chamber to seal at least one of the through holes for forming a suction region of the suction wheel member.
摘要:
A light emitting diode includes a first conductivity type semiconductor substrate, a basic AlGaInP double heterostructure and two window layers of second conductivity type semiconductor. A layer of first conductivity type AlGaInP an undoped AlGaInP layer and a layer of second conductivity type AlGaInP form the double heterostructure. The AlGaInP layers are epitaxially grown above the substrate sequentially. The window layers contain one layer of GaAs and the other layer of GaP. The first window layer is formed by epitaxially growing GaAs over the AlGaInP heterostructure. The second window layer is formed by growing GaP directly on the first window layer using either OMVPE or vapor phase epitaxy (VPE) technology. The inclusion of a GaAs window layer increases current spreading and, hence, the efficiency of the device. The yield rate of manufacturing the light emitting diode is also increased because the quality of GaP layer surface is improved.
摘要:
The present invention provides a semiconductor light emitting device which includes a multi-layer structure. Additionally, an electrode is disposed on a first surface of the multi-layer structure. Furthermore, the electrode includes a plurality of bonding pads.
摘要:
The present invention provides a method for fabricating a flip chip semiconductor light-emitting device which includes a substrate and a semiconductor multi-layer structure. The method of the invention includes the steps of: (a) forming a semiconductor multi-layer structure on a first substrate; (b) flip-chip bonding the semiconductor multi-layer structure on a second substrate; (c) removing the first substrate, so as to expose a first surface of the semiconductor multi-layer structure; and (d) forming a plurality of protrusions, arranged periodically, on the first surface. Particularly, the protrusions comprise a first protrusion and a second protrusion adjacent to the first protrusion, the first protrusion and the second protrusion both having a peak, and the second surface having a bottom, wherein the ratio of the vertical distance between one of the peaks and the bottom and the horizontal distance between the two peaks is in between 0.01 and 10.
摘要:
The present invention is to provide a semiconductor device which includes a mounting base and a light-emitting device. The mounting base includes a substrate of a first semiconductor material and a first layer of a material with high thermal conductivity formed over the substrate. Furthermore, the light-emitting device is a multi-layer structure which includes at least a second layer of a second semiconductor material. The light-emitting device is mounted on the first layer of the mounting base. Moreover, the difference of the thermal expansion coefficient between the first semiconductor material and the second semiconductor material is between a predetermined range.
摘要:
A light emitting diode is epitaxially grown on a semiconductor substrate. A lower cladding layer is grown on the substrate and doped to have n-type conductivity. An active layer is deposited on the lower cladding layer, and a p-type upper cladding layer is deposited on the active layer. A relatively thin lower window layer is then deposited on the upper cladding layer, and doped with a first p-type dopant material. A relatively thick upper window layer is then deposited on the lower window layer, and doped with a different p-type dopant material. The layer with a dopant different from the principal portion of the window serves to limit diffusion of dopant through the active layer. The dopant in the diffusion limiting layer can diffuse in both directions, thereby reducing the driving force of diffusion. As a result, the p-type dopant intersects a steep portion of the concentration gradient of n-type dopant quite near the interface between the lower cladding layer and active layer, resulting in high light output power. A diffusion limiting layer having a different dopant than a substrate may be used for forming a LED with a p-type substrate and an n-type layer near the upper face.
摘要:
A light emitting diode (LED) including a light generation region situated on a light-absorbing substrate also includes a thick transparent layer which ensures that an increased amount of light is emitted from the sides of the LED and only a minimum amount of light is absorbed by the substrate. The thickness of the transparent layer is determined as a function of its width and the critical angle at which light is internally reflected within the transparent layer. The thick transparent layer is located either above, below or both above and below the light generation region. The thick transparent layer may be made of materials and with fabrication processes different from the light generation region.