61results about How to "Improve wavelength uniformity" patented technology

In an optical branching unit according to the invention, the cross section shape in an area of a front stage to branch to two output waveguides in the optical branch is a rectangle or a non-circle with different vertical-to-horizontal ratio, including an area that the length along the surface of the substrate is defined to be shorter than the length in the direction orthogonal to the surface of a substrate, the cross section at the output ends of the output waveguide is a rectangle or a non-circle with a different vertical-to-horizontal ratio, where the length along the surface of the substrate is defined to be longer than the length in the direction orthogonal to the surface of the substrate.

A gallium nitride based semiconductor device includes a silicon-based layer doped simultaneously with boron (B) and germanium (Ge) at a relatively high concentration, a buffer layer on the silicon-based layer, and a nitride stack on the buffer layer. A doping concentration of boron (B) and germanium (Ge) may be higher than 1×1019 / cm3.

The invention discloses a pattern-segmented sapphire substrate used for AlGaInN material system film growth. The pattern-segmented sapphire substrate comprises a sapphire substrate body; pattern segmentation grooves divide the upper surface of the sapphire substrate body into a plurality of mutually-independent repeated pattern units, wherein the pattern units are growing platforms of AlGaInN materials. The sapphire substrate body is a plane sapphire substrate body or a pattern sapphire substrate body. The pattern segmentation grooves are trench-type pattern segmentation grooves or second medium-type pattern segmentation grooves. The pattern-segmented sapphire substrate is formed by dividing the sapphire substrate into the plurality of mutually-independent and mutually-isolated pattern units through the grooves or second medium. According to the segmented AlGaInN epitaxial thin films, the wave length uniformity of an LED can be greatly improved, the qualified rate of an LED epitaxial wafer is improved, and the giant thermal stress and thermal shock, due to laser lift-off, between the AlGaInN epitaxial thin films and the sapphire substrate are greatly reduced, the pass rate of the laser lift-off can be greatly improved, and the qualified rate of sapphire substrate vertical structure LED chips is improved.

The invention discloses a semiconductor light emitting diode and a manufacturing method thereof. The method includes: forming a crystalline nitride semiconductor layer on a substrate; forming an amorphous layer and a crystalline nitride semiconductor layer on the nitride semiconductor layer; forming an n-type nitride semiconductor layer on the crystalline nitride semiconductor layer; forming an active layer on the compound semiconductor layer; and forming a p-type nitride semiconductor layer on the active layer.

The present invention proposes a method for preparing light-emitting elements. Gallium nitride is grown on a flat sheet or pattern substrate that has been plated with AlN, and then an H2 atmosphere annealing treatment or a combined H2 atmosphere and NH3 atmosphere heat treatment is performed to change and buffer. The problem of stress between materials can be improved, and the warpage of the epitaxial wafer caused by this stress can be improved, the epitaxial quality of the light-emitting element can be improved, and the luminous efficiency of the light-emitting element can be improved.

The invention discloses a method for manufacturing a light-emitting diode chip, which comprises the following steps: firstly forming a corridor on the surface of a growth substrate, dividing the surface of the growth substrate into a small region which is in the same size with the final chip, and defining the size of the chip; then cleaning the growth substrate, and removing dirt in a ditch of the growth substrate; further producing a patterned substrate on the growth substrate after dividing; and finally sequentially growing an N-type semiconductor layer, an active layer and a P-type semiconductor layer on the patterned substrate for forming a single chip structure consisting of the mutually separated N-type semiconductor layer, the active layer and the P-type semiconductor layer. The process method can reduce the residual stress during the epitaxial growth process, reduce the crystal defects and be further conductive to improving the wavelength uniformity of the chip, improving the electric leakage of the chip and improving the brightness of the chip.

The present invention provides a method for manufacturing an LED epitaxial wafer, which includes the following steps: step 3: making a plurality of convex cones at intervals on the AlN layer; step 4: making a plurality of concave and inverted cones at intervals on the AlN layer Cavity, the conical cavity and the cone are staggered and not connected to each other; step 5, periodically grow a plurality of multiple quantum well light-emitting layers on the AlN layer, each of the multiple quantum well light-emitting layers includes sequentially grown InGaN The well layer and the GaN barrier layer, wherein the multi-quantum well light-emitting layer grown in the first cycle is used to fill the conical cavity in the step 4, and starting from the second cycle, the multi-quantum well light-emitting layer grown in the subsequent cycle is located in On the overall structure including the AlN layer and the multiple quantum well light-emitting layer grown in the previous cycle. The invention can improve the brightness of the LED epitaxial wafer, enhance the antistatic ability, improve the wavelength concentration, and can also reduce the forward voltage of the LED epitaxial wafer.