37results about How to "Improved current spread" patented technology

The invention provides the epitaxial device of a semiconductor light emitting diode. The device comprises an N electrode, an N-type semiconductor contact layer, an N-type semiconductor conducting layer, a luminescent layer, a P-type semiconductor conducting layer, a P-type semiconductor contact layer and a P electrode which are successively contacted with each other. An interface contact resistance between the N electrode and the N-type semiconductor contact layer is adjusted by the doping concentration of the N-type semiconductor contact layer. Or an interface contact resistance between the Pelectrode and the P-type semiconductor contact layer is adjusted by the doping concentration of the P-type semiconductor contact layer. In the invention, in an interface where the surface of a semiconductor is contacted with a metal electrode, current expansion is improved; because the contact of metal and the semiconductor is sensitive, the electric conductivity of the interface is easy to adjust and control, and only a thin layer is needed in an epitaxy so that the current expansion can be greatly improved; and the ascending range of a device voltage is small.

The disclosure provides an epitaxial wafer of an ultraviolet light-emitting diode and a preparation method thereof, belonging to the field of light-emitting diodes. The epitaxial wafer includes: a substrate and a low-temperature buffer layer sequentially stacked on the substrate, a first undoped AlGaN layer, an N-type semiconductor layer, an active layer, and a P-type semiconductor layer, and the N-type semiconductor layer including a highly doped N-type layer and a low-doped N-type layer sequentially stacked on the first undoped AlGaN layer, and the low-doped N-type layer includes stacking on the highly doped N-type layer The first low-doped layer, the highly-doped N-type layer and the first low-doped layer both include a plurality of AlGaN layers and a plurality of SiN layers alternately distributed, and Si in the highly-doped N-type layer The doping concentration is higher than the Si doping concentration in the low-doped N-type layer. The present disclosure can improve the electrical performance of the ultraviolet light emitting diode.

The invention discloses a III-group nitride light-emitting diode (LED) and a manufacturing method thereof. The LED comprises a substrate and a semiconductor epitaxial laminate which is laminated on the substrate, wherein the semiconductor epitaxial laminate sequentially comprises an N type layer, a luminescent layer and a P type layer from top to bottom. The LED is characterized in that: an N type layer table face is formed in the N type layer by etching a part of the semiconductor epitaxial laminate; an N type electrode is arranged on the N type layer table face; a P type electrode is arranged on the upper surface of the un-etched part of the P type layer; the N type layer also comprises a uniformly doped layer of which the doping concentration is consistent and a modulation doped layer of which the doping concentration is changeable; and the modulation doped layer is arranged between the uniformly doped layer and the luminescent layer. A doped mode of the modulation doped layer is gradual transition doping which connects uniformly doped layer and the luminescent layer of which the doping concentration is consistent. The concentration change trend is decrease progressively change from the uniformly doped layer to the luminescent layer. By the LED and the manufacturing method, the crystal quality and the luminance uniformity can be obviously improved, and the lighting effect is improved.

The invention discloses a high-brightness light-emitting diode based on an AIN / PSS composite substrate and a preparation method of the high-brightness light-emitting diode. The high-brightness light-emitting diode comprises the AlN / PSS composite substrate, a u-type GaN merging layer, an n-type GaN layer, a low-temperature GaN V-pits layer, an active region, an electron blocking layer, a high-temperature p-type GaN layer and a contact layer which are sequentially stacked from bottom to top. The high-brightness light-emitting diode provided by the invention comprises the u-GaN merging layer of anovel structure, the V-pits layer and the active region; and therefore, the crystal quality of an epitaxial layer can be effectively improved, the stress of the active region can be effectively relieved, current expansion in a horizontal direction can be improved, the light-emitting efficiency of the light-emitting diode can be improved, and the brightness of the prepared light-emitting diode ishigh.

A reverse polarity vertical light emitting diode and its preparation method, the reverse polarity vertical light emitting diode comprises: a substrate; an n-type electrode located on the substrate; an n-type GaN-based semiconductor layer located on the n-type electrode the light-emitting layer is located on the n-type GaN-based semiconductor layer; the p-type GaN-based semiconductor layer is located on the light-emitting layer; the p-type electrode is located on the p-type GaN-based semiconductor layer; The n-type GaN-based semiconductor layer, light-emitting layer and p-type GaN-based semiconductor layer all show nitrogen polarity in the bottom-up direction, and show metal polarity in the top-down direction. The present invention integrates the advantages of reverse polarity and vertical structure, can effectively increase the hole concentration of the p-type GaN-based semiconductor layer, suppress the quantum-confined Stark effect in the active region of the quantum well, thereby improving the radiation recombination efficiency and internal quantum of the LED Efficiency, improving the luminous performance and reliability of LEDs.

The invention discloses a light emitting diode epitaxial wafer and a preparation method thereof, and belongs to the technical field of semiconductors. The light-emitting diode epitaxial wafer comprises a substrate, an N-type semiconductor layer, a stress release layer, an active layer and a P-type semiconductor layer, wherein the N-type semiconductor layer, the stress release layer, the active layer and the P-type semiconductor layer are sequentially stacked on the substrate; the stress release layer comprises a plurality of composite structures which are stacked in sequence, wherein each composite structure comprises a first sub-layer, a second sub-layer, a third sub-layer and a fourth sub-layer which are stacked in sequence; the first sub-layer is made of non-doped indium gallium nitride, the second sub-layer is made of non-doped aluminum nitride, the third sub-layer is made of silicon nitride, and the fourth sub-layer is made of non-doped gallium nitride. According to the light-emitting diode epitaxial wafer, the photoelectric property of the LED is finally improved.

The invention discloses a vertical high-voltage light-emitting diode chip and a manufacturing method thereof, wherein. Through the design of the vertical high voltage light emitting diode chip, the back electrode at the first chip area is electrically connected to the conductive substrate through the opening and the bonding layer, so that the back electrode is exposed without etching in the first chip area, so as to ensure the vertical high voltage light emitting diode. The effective light-emitting area of ​​the chip is large; and, the back electrode of the first chip area does not need to be wired, which saves costs and improves reliability; in addition, the current expansion of each chip area is in the vertical direction, and the first chip area The back electrode and the front electrode of the Nth chip area form a vertical structure, so that the current of the vertical high-voltage light-emitting diode chip expands better, thereby avoiding current congestion and improving the current tolerance; in addition, the vertical high-voltage light-emitting diode chip has a better light type , which conforms to the Lambertian distribution and is easier to light distribution.