38results about How to "Reduce thermal mismatch" patented technology

Embodiments for minimizing relative thermal growth within a fuel nozzle of a gas turbine combustor are disclosed. Fuel nozzle configurations are provided in which a heating fluid is provided to one or more passages in a fuel nozzle from feed holes in the fuel nozzle base. The heating fluid passes through the fuel nozzle, thereby raising the operating temperature of portions of the fuel nozzle to reduce differences in thermal gradients within the fuel nozzle. Various fuel nozzle configurations and passageway geometries are also disclosed.

The present disclosure discloses a method for transferring micro-light emitting diodes, a micro-light emitting diode device and an electronic device. The method for transferring micro-light emitting diodes comprises: providing bumps of bonding agent on electrode bonding pads of a receiving substrate and / or on micro-light emitting diodes of an original substrate; aligning and contacting the electrode bonding pads of the receiving substrate and the micro-light emitting diodes of the original substrate, to position the bumps of bonding agent between the micro-light emitting diodes and the electrode bonding pads; irradiating locally by using a first laser from the original substrate side, to melt the bumps of bonding agent to bond the micro-light emitting diodes and the electrode bonding pads;and stripping off the micro-light emitting diodes from the original substrate, to transfer the micro-light emitting diodes to the receiving substrate. The present disclosure, by heating quickly and locally by laser irradiation, avoids the overall warming-up of the receiving substrate and the original substrate, reduces the heat mismatch phenomenon, optimizes the flow of the bonding of the micro-light emitting diodes, and facilitates the controlling.

The invention discloses a Sm-Gd-Dy tri-rare-earth ion tantalate and a preparation method and application thereof. The general chemical formula of the Sm-Gd-Dy tri-rare-earth ion tantalate is SmGdDy<c>TaO<7>, wherein the a, b and c meet the relationship of a+b+c=3 and are separately in a range of 0.8-1.2. The preparation method comprises the following steps: (1) weighing samarium nitrate, gadolinium nitrate, dysprosium nitrate and tantalum oxalate according to a stoichiometric ratio, performing mechanical mixing with citric acid with a preset amount under a heat preservation condition, adding a concentrated ammonia water neutralization solution during the mixing process, and carrying out mechanical mixing to promote a complexation reaction under a heat preservation condition; and (2)drying the obtained solution, and then carrying out calcination at a high temperature to remove carbon impurities to obtain the Sm-Gd-Dy tri-rare-earth ion tantalate powder. The Sm-Gd-Dy tri-rare-earth ion tantalate has good high-temperature thermal stability and low thermal conductivity, and can be used as a thermal barrier coating material.

The invention discloses a low-temperature epitaxy preparation method of a germanium-silicon film with high germanium content. The low-temperature epitaxy preparation method comprises the following specific steps: (1) providing a silicon substrate with a (100) crystal face; (2) carrying out deoxidation on the silicon substrate at the temperature of 1350 DEG C, wherein the deoxidation lasts for 10 minutes; (3) through a molecular beam epitaxy method, growing a silicon buffer layer with the thickness of 20 to 50 nm on the silicon substrate after deoxidation, wherein the growth temperature is 700 DEG C; and (4) cooling the silicon buffer layer to a growth temperature which is below 300 DEG C, then growing GexSi1-x alloy, and adjusting the content of Ge, namely an x value, by changing the growth rates of Ge and Si. According to the preparation method, the high-quality germanium-silicon (GexSi1-x) film material with adjustable lattice constants can be directly grown on the silicon wafer at low temperature, and the content of germanium at most can reach 83%. The method does not need to adopt a layer-by-layer growth pattern for improving the content of germanium layer by layer, so that the method is simpler in operation and lower in cost.

The invention discloses a C / C-SiC-ZrC-TiC composite material and a preparation method thereof. The composite material is composed of a carbon fibre, a pyrolytic carbon, a main matrix phase ZrC-TiC and a sub matrix phase SiC. The composite material is characterized in that the SiC is used as an interface layer for separating the pyrolytic carbon from the ZrC-TiC. The preparation method comprises the following steps: melting the mixed powder of Zr, Ti and Si, permeating into the inside of the low-density C / C composite material through a capillary action, forming a ceramic phase in a hole through an in situ reaction to obtain the C / C-SiC-ZrC-TiC composite material. The preparation method is rapid and effective and low in cost; the prepared composite material has excellent super-high temperature ablation resistance performance and simultaneously has excellent strength, breaking tenacity and thermal shock resistance.

The invention provides a manufacturing method for a semiconductor device. The manufacturing method comprises: a semiconductor substrate is provided and a groove for forming a through silicon via is formed in the semiconductor substrate; a protection layer that covers the side wall and the bottom of the groove and is used for absorbing a swelling stress is formed; at least one transition layer is formed on the protection layer; and the groove is filled by metallic copper, wherein the transition layer employs a metal material and the thermal expansion coefficient of the transition layer is smaller than that of the copper. According to the manufacturing method, the metal material having the small thermal expansion coefficient is added between the silicon and cooper during the through silicon via forming process to form the transition layer between the Si / Cu, so that the thermal mismatching between the two kinds of materials is reduced; the thermal expansion coefficient is increased gradually from the transition layer to the metallic copper layer, thereby reducing the thermal mismatching among all materials at all layers effectively and thus avoiding layering or copper layer protrusion.

The invention discloses a low-temperature glass solder bonding and packaging method based on wafer-level glass microcavities, which comprises the following steps: firstly, utilizing a silk-screen printing process to coat low-temperature glass solder on a packaging contact part of a Pyrex7740 glass substrate provided with a microcavity structure, preliminarily drying the low-temperature glass solder, and making the low-temperature glass solder be cured and cling to the Pyrex7740 glass substrate provided with the microcavity structure; secondly, aligning a Pyrex7740 glass packaging wafer which is cured with the low-temperature glass solder and a silicon substrate wafer comprising an MEMS device or a CMOS circuit, and making the microcavity structure on the Pyrex7740 glass substrate correspond to the position of the MEMS device or the CMOS circuit to be packaged of a silicon substrate; and thirdly, using a clamper to firmly clamp the two aligned wafers, applying the pressure, sintering the glass solder in a specified packaging atmosphere, and cooling the glass solder. The whole process is based on integral processing of the silicon wafer and the Pyrex7740 glass wafer, belongs to a process for manufacturing and packaging a wafer-level MEMS, and has the characteristics of simple method, adjustable packaging space and low cost.

The invention discloses anti-oxidation ZrB on the surface of C-C composite material 2 ‑SiC‑Y 2 O 3 ‑SiC coating and method of making the same. First, a SiC transition layer was prepared on the surface of the C-C composite matrix by embedding and infiltration technology, and ZrB was prepared on the SiC transition layer by embedding and infiltration. 2 ‑SiC‑Y 2 O 3 outer coating. in ZrB 2 ‑SiC‑Y 2 O 3 The introduction of a SiC transition layer between the coating and the substrate can alleviate the mismatch of thermal expansion coefficients, release thermal stress, and further improve the oxidation resistance of the coating. The present invention adopts two-step embedding and infiltration technology to prepare ZrB 2 ‑SiC‑Y 2 O 3 ‑SiC composite coating has little thermal damage to the C‑C substrate, strong bonding force of the coating, and dense coating. The SiC transition layer effectively relieves the mismatch between the thermal expansion coefficients of the outer coating and the substrate, reduces the cracking of the outer coating due to thermal stress, improves the bonding force of the coating, and effectively improves the oxidation resistance of the coating.

The invention discloses a MEMS capacitive air pressure sensor based on PN junction electrical isolation and anodic bonding technology, comprising an air pressure sensitive film, a glass substrate and a glass cover plate; one side of the air pressure sensitive film is anodically bonded with the glass substrate to form a vacuum reference chamber , the other side of the air pressure sensitive film is anodically bonded with the glass cover to form an open gas pressure sensitive film, the external air pressure is applied to the air pressure sensitive film, and the pressure difference with the vacuum reference chamber forms a pressure difference to deform the air pressure sensitive film, and then changes the air pressure sensitive film The distance between the capacitive plate and the glass substrate changes the capacitance value to reflect the external air pressure. The invention also discloses the processing technology of the MEMS capacitive air pressure sensor. The capacitive air pressure sensor of the invention has simple processing technology, high yield rate and good commercialization effect.

The present disclosure provides a method for preparing a group III oxide thin film based on a chamfered corner substrate and an epitaxial wafer thereof, the preparation method comprising: epitaxial buffer layer (2) on a continuous stepped substrate (1) with chamfered corners; An epitaxial layer (3) is prepared on the buffer layer (2); wherein, the epitaxial layer (3) is a single crystal Group III oxide thin film, the buffer layer (2) and the substrate (1) are heterogeneous, and the buffer layer (2) and The epitaxial layer (3) is homogeneous. By epitaxial buffer layer on a continuous atomic-level stepped substrate with chamfered corners, the adatoms of the reaction source can be promoted to grow at the edge of the step to form a growth pattern with consistent orientation, and a complete single-crystal buffer layer film can be obtained. A high-quality single-crystal epitaxial layer film is homoepitaxially grown on the single-crystal buffer layer film. The method has strong process compatibility, reduces the cost of producing high-quality single crystal group III oxide thin films, and facilitates its popularization and use.

The invention relates to the technical field of high-temperature infrared stealth materials, and specifically discloses an anti-oxidation / infrared stealth coating on the surface of a fiber-reinforced ceramic matrix composite material with a temperature resistance of 1650°C. The infrared stealth coating has a layered structure, which consists of A ceramic inner layer, a ceramic middle layer, a ceramic outer layer and a low infrared emissivity functional layer, the ceramic inner layer is a mullite layer, the ceramic middle layer is a rare earth silicate layer, and the ceramic outer layer is an 8YSZ layer , the low infrared emissivity functional layer is based on Pt as the conductive phase, Bi 2 o 3 coating for the binder phase. The invention also provides a preparation method for the anti-oxidation / infrared stealth coating on the surface of the fiber-reinforced ceramic matrix composite material with a temperature resistance of 1650°C. The infrared stealth coating of the invention improves the oxidation resistance and high temperature stability of the composite material, can significantly reduce the infrared radiation intensity of the base material, and has excellent oxidation resistance and infrared stealth function.

The invention relates to a low-heat-dissipation motorcycle engine manufacturing method. The manufacturing method includes the following steps that a piston, an air cylinder cover and an air cylinder body of an engine are subject to ultrasonic cleaning, and a spraying zone is subject to sand blasting through No.40 corundum gravels after washing is finished; a low temperature high velocity flame spraying is adopted for spraying the top surface of the piston and the inner surface of the air cylinder cover to form NiCoCrAlYTa bonding layers, and atmospheric plasma spraying is adopted for spraying the outer surface of the air cylinder body to form a NiCrAl bonding layer; and after the bonding layers are formed through spraying, the top surface of the piston, the inner surface of the air cylinder cover and the outer surface of the air cylinder body are subject to 7YSZ ceramic layer atmosphere plasma spraying. By means of the manufacturing method, through compounding of a ceramic material and a metal material, advantages of the two kinds of materials can be integrated, the defect that in the prior art, a view is given to manufacture pure ceramic engine parts is overcome, and therefore a motorcycle engine which is low in cost, high in heat isolation, resistant to oxidation, resistant to corrosion and long in service life is obtained.

The invention provides a mid-infrared band modulator preparation method. The method comprises the steps that 1, vacuum bonding is conducted on an SOI substrate top silicon (1) and an N-type InSb substrate (20); 2, the N-type InSb substrate (20) is thinned and then etched to obtain a ridge N-type InSb structure (2) which includes the ridge in the middle and flat areas on the two sides; 3, the flatareas are transformed into a P-type InSb structure (3), or the ridge protruding out of the flat areas is transformed into the P-type InSb structure (3), and meanwhile a neutral area I (4) is formed between the N-type InSb structure (2) and P-type InSb structure (3); 4, photoetching corrosion is conducted on the flat area on one side of the ridge, and the flat area on the other side of the ridge isretained; 5, a passive protective layer (5) is prepared; 6, an N electrode (6) and a P electrode (7) are prepared. The invention further provides a mid-infrared band modulator.