41results about How to "Reduce the difficulty of growing" patented technology

The invention discloses a multi-wavelength semiconductor laser based on an annular resonant cavity and belongs to the field of semiconductor lasers. The multi-wavelength semiconductor laser comprises a substrate layer, a buffer layer, a lower cladding, an active layer, an upper cladding and an ohmic contact layer which are arranged from bottom to top, wherein the laser is provided with more than one annular ridge waveguide and a coupled waveguide, each annular ridge waveguide is formed by at least the ohmic contact layer and part of the upper cladding or the whole upper cladding and can generate laser beams under forward bias, and the coupled waveguide can amplify the optical power of the laser beams under forward bias; the annular ridge waveguide and the active layer form the annular resonant cavity; the circumferences of the annular ridge waveguides are not equal; and the coupled waveguide is arranged adjacent to the annular ridge waveguides. The multi-wavelength semiconductor laser based on the annular resonant cavity has the advantages that the multi-wavelength semiconductor laser is simple and compact in structure and is easy in integration with other devices; the process is simplified, and the cost is lowered; the superposition of active layers of a plurality of single longitudinal-mode lasers is avoided, and the difficulty in the growth of materials is reduced; and the output paths of the laser beams are flexible and adjustable, and the large-scale integration of lasers is easily implemented.

The invention discloses an epitaxial growth method with a p-layer special doped structure. According to the method, when a p-type layer of an LED (Light Emitting Diode) is grown, double-element doping of a GaN / AlGaN superlattice structure is adopted, that is, a small amount of silane is doped when doping magnesium. The silane is doped as a donor, however, due to the small amount of the doped silane, the lattice imperfection caused by the doped magnesium can be remarkably improved, a self-compensation effect is reduced, the crystal quality is improved, non-composite imperfection centers are reduced, a small number of scattering centers are caused, the carrier mobility and the ionization efficiency of an accepter are improved, and in addition, as the growing temperature of AlGaN is high, such doping is beneficial for improving the doping concentration of magnesium, the doping effect of the p-layer is improved, and the overall lighting efficiency of the LED is greatly improved. Due to improvement of the crystal quality and the improvement of barrier layer conductivity, the current expansion capability is improved, and the reliability of the LED device is also improved.

The invention discloses a Si-based vertical cavity surface emitting chip. The structure consists from bottom to top of an n-type electrode, a substrate, a buffer layer, a lower distributed Bragg reflector located on the substrate, active area located on the lower distributed Bragg reflector, an upper distributed Bragg reflector located on the active area, a p-type electrode located on the upper distributed Bragg reflector, and a SiO2 confinement layer located around a cylindrical mesa. In the invention, a silicon-doped (AlxGa1-x)2O3, (AlyGa1-y)2O3 stacked structure is prepared on an n-type silicon substrate as the lower distributed Bragg reflector, rare earth-doped Ga2O3 is used as an n-type luminous material, and a GaAs, AlGaAs or InP, InGaAsP stacked structure is used as the upper distributed Bragg reflector. As a silicon-based vertical cavity surface emitting light source according to the invention, the characteristics of high thermal stability, high chemical stability, simple preparation method and high reliability are gained.

The invention provides a semiconductor epitaxial structure, VCSEL and manufacturing method based on a flexible substrate. Fluorphlogopite mica is used as the substrate, which not only solves the problem that the existing semiconductor substrate cannot be bent and is not easy to peel off, but also takes into account the cost of the semiconductor device. temperature requirements. For the buffer layer, the multi-layer first GaInP buffer layer is gradually changed layer by layer, showing a step gradient trend. By inserting the second layer of the In composition gradient opposite to the direction of the In composition gradient between two adjacent first GaInP buffer layers. The GaInP buffer layer forms a structure with fluctuating and gradual changes in the In composition, thereby introducing compressive stress in the buffer layer, increasing the interaction of dislocations, making the surface smoother, and further reducing threading dislocations, improving the performance of fluorine phlogopite. The quality of the epitaxial layer on the substrate realizes the application of fluorophlogopite substrate in semiconductor devices. VCSEL has the advantages of being bendable, easy to peel off, good epitaxial layer quality, and high light extraction efficiency.

The invention relates to a long-wave infrared space modulation interference miniaturizing method. The method is characterized in that an interference assembly is composed of a spectroscope, a pyramid reflector I, a pyramid reflector II and two aperture diaphragms; an included angle between the spectroscope and parallel incident light is 135degree; from the optical axis position of reflected light, the top position of the pyramid reflector I starts to move anticlockwise for 1 / 4 transverse shear amount along the direction vertical to the optical axis of the reflected light; from the optical axis position of transmitted light, the top position of the pyramid reflector II starts to move anticlockwise for 1 / 4 transverse shear amount along the direction vertical to the optical axis of the transmitted light; and the two aperture diaphragms are respectively arranged at the top positions of the two pyramid reflectors, and are respectively placed vertical to the optical axes of the reflected light and the transmitted light. Under the condition that optical parameters are consistent, the size of the spectroscope is decreased, the sizes of the interference assembly and a spectrometer are effectively controlled, the difficulties in material growing and processing are reduced, and the cost is saved.

The invention provides a method for improving the reliability of a gate oxide layer of a peripheral circuit area of a flash memory. The method includes the following steps that: oxidation treatment is performed on a nitrogen containing region of the top of a semiconductor substrate at the peripheral circuit area; and the nitrogen containing region is converted into an oxide layer, and the oxide layer is removed, and therefore, a nitrogen-free semiconductor substrate surface of the peripheral circuit area is exposed; and a gate oxide layer is grown on the nitrogen-free semiconductor substrate surface. With the method adopted, when an MOS device is manufactured in the peripheral circuit area in a subsequent process, the nitrogen containing region of the top of the semiconductor substrate is removed, and therefore, the growth difficulty of the gate oxide layer on the surface of the semiconductor substrate can be lowered, and especially, the growth capacity of the gate oxide layer on the semiconductor substrate at corners of an isolation structure can be improved, and the integrity and uniformity of gate oxide layer growth can be increased, and the reliability of the gate oxide layer of the MOS device can be improved; and the oxidation treatment mentioned in the invention is performed at room temperature or low temperature, and therefore, thermal budget in the prior art can be decreased, and device doping profile shift can be avoided. The method is advantageous in convenient implementation and simple operation.

The invention belongs to the technical field of nano-pillar LED preparation, and discloses a nano-pillar LED grown on a strontium tantalum lanthanum aluminate substrate and a preparation method thereof. The nano-pillar LED grown on a strontium tantalum lanthanum aluminate substrate comprises a strontium tantalum lanthanum aluminate substrate, an AlN nucleation layer grown on the strontium tantalum lanthanum aluminate substrate, a GaN nano-pillar template grown on the AlN nucleation layer, an AlN / GaN super lattice layer grown on the GaN nano-pillar template, a non-doped GaN layer grown on the AlN / GaN super lattice layer, an n-type doped GaN layer grown on the non-doped GaN layer, an InGaN / GaN quantum well grown on the n-type doped GaN layer, and a p-type doped GaN layer grown on the InGaN / GaN quantum well. The substrate material is of low cost. A nano-pillar array prepared is size-controllable and of uniform orientation. The obtained nano-pillar LED has low defect density and excellent electrical and optical properties.