750 results about "Low-k dielectric" patented technology

The present invention relates to an intrinsically high thermal conductivity-low dielectric polyimide film, its preparation method, and applications. The polyimide is composed of polyimide A and polyimide B through blending or grafting. The polyimide film of the present invention has intrinsically high thermal conductivity, low dielectric constant and loss, and excellent heat resistance and mechanical properties. It has broad application prospects in integrated circuits, electronic packaging, and other fields.

The present disclosure describes a method for forming a nitrogen-rich protective layer within a low-k layer of a metallization layer to prevent damage to the low-k layer from subsequent processing operations. The method includes forming, on a substrate, a metallization layer having conductive structures in a low-k dielectric. The method further includes forming a capping layer on the conductive structures, where forming the capping layer includes exposing the metallization layer to a first plasma process to form a nitrogen-rich protective layer below a top surface of the low-k dielectric, releasing a precursor on the metallization layer to cover top surfaces of the conductive structures with precursor molecules, and treating the precursor molecules with a second plasma process to dissociate the precursor molecules and form the capping layer. Additionally, the method includes forming an etch stop layer to cover the capping layer and top surfaces of the low-k dielectric.

The invention discloses a bending-resistant and low-dielectric transparent polyimide film for a flexible electronic device as well as a preparation method and application of the bending-resistant and low-dielectric transparent polyimide film. The surfaces of glass beads are subjected to grafting modification treatment by adopting alkali liquor and a coupling agent; performing ultrasonic dispersion to uniformly disperse the grafted and modified glass beads in a solvent; the preparation method comprises the following steps: dissolving a fluorine-containing diamine monomer in a solvent containing graft modified glass beads under a nitrogen protection atmosphere, after the fluorine-containing diamine monomer is completely dissolved, slowly adding a fluorine-containing dianhydride monomer in batches under a continuous stirring condition, and preparing a transparent polyamide acid solution containing glass beads through a condensation polymerization reaction; and uniformly coating the polyamide acid solution containing the glass beads on a glass substrate through a blade coating machine, and then carrying out gradient heating to obtain the glass bead compounded transparent polyimide film. Fluorine atoms are introduced into molecular structures of dianhydride and diamine, and grafting modified glass beads are doped to serve as filler, so that the transparent polyimide film with bending resistance and low dielectric constant characteristics is successfully prepared.

The invention discloses a low-dielectric polyimide film material and a preparation method and application thereof, and relates to the technical field of film material preparation, and the molecular structure of a polyimide copolymer in the polyimide film material comprises structural units shown in general formulas (1) and (2), the polyimide copolymer comprises aromatic ether, fluorine atoms or fluorine-containing groups and siloxane units, at least one of C and D in the structural units contains fluorine atoms or fluorine-containing groups, and the molar ratio of the content of the copolymerization components x: y: z is (1-90%): (1-50%): (1-30%). According to the preparation method, a batch feeding synthesis mode is adopted, molecular chain growth of polyamide acid is controlled through the feeding ratio, the salt forming effect of silicon-containing diamine and polyamide acid is avoided, and high-molecular-weight polyimide is obtained. The polyimide film prepared by the method has the characteristics of low dielectric constant and dielectric loss, low water absorption, good adhesion and the like, and can be applied to the fields of high-frequency and high-speed integrated circuits and the like.

The invention relates to aluminum borosilicate glass with low dielectric constant and low dielectric loss and a preparation method and application thereof, and relates to the field of aluminum borosilicate glass manufacturing, the aluminum borosilicate glass comprises the following main components by molar percentage: 60%-85% of SiO2, 0-10% of Al2O3, 2%-30% of B2O3, 0-20% of alkaline earth oxide, 0-10% of alkali metal oxide, 0-10% of ZnO, 0-1% of P2O5 and 0-2% of TiO2 and / or ZrO2; during preparation, the raw materials are melted, clarified and homogenized according to the corresponding dosage, and then are annealed for 3-8 hours at the temperature of 600-650 DEG C. The obtained aluminum borosilicate glass can reduce transmission loss during high-frequency signal transmission, has dielectric constant stability which does not exceed + / -0.5 change under a 1-30 GHz signal test, and can be applied to preparation of integrated antennas, electronic packaging and micro electro mechanical system packaging.

According to the printed circuit board and the preparation method thereof provided by the invention, the glass core plate is used for replacing a traditional resin material, and the characteristics of low thermal expansion coefficient, low humidity coefficient and low dielectric constant of the glass core plate are utilized, so that warping and signal interference caused by temperature change and environment humidity are effectively reduced, and the stability and reliability of the PCB are remarkably improved. Meanwhile, by repeatedly constructing a multilayer layer-adding structure, adopting an ABF layer at the position adjacent to the glass substrate and adopting dielectric layers with Dk < = 3.0 and Df < = 0.001 for the rest, signal attenuation and interference can be effectively reduced, signal integrity and transmission efficiency can be ensured, overall buckling deformation of the PCB structure can be reduced or even avoided, and the PCB structure is more stable in performance. The multi-layer adding meets the requirements of different application scenarios for the number of layers of the PCB, improves the flexibility and applicability of the PCB, and enables the PCB to be especially suitable for the application scenarios of high-frequency and high-speed signal transmission.

The invention discloses a low dielectric constant temperature-stable phosphate microwave dielectric ceramic material for LTCC and a preparation method thereof, the chemical composition formula of the phosphate microwave dielectric ceramic material is A3-xK2x (PO4) 2, A = Ba1-ySry, x is more than or equal to 0.1 and less than or equal to 0.5, y is more than or equal to 0 and less than or equal to 1, and the phosphate microwave dielectric ceramic material comprises two phases of A3 (PO4) 2 and KAPO4; the preparation method comprises the following steps: regulating and controlling the A-site ion radius of A3 (PO4) 2-based ceramic, pre-sintering to directly synthesize complex-phase powder containing phases A3 (PO4) 2 and KAPO4 in situ in one step, then adding H3BO3 powder accounting for 1-5% of the total mass of a base material, and carrying out ball milling, drying, sieving, forming, rubber discharging and sintering to obtain a ceramic sample; the ceramic material has a low sintering temperature (850-950 DEG C), a low dielectric constant (epsilon r = 8.9-12.6), a high quality factor (Q * f = 10186-50213 GHz) and a near-zero temperature resonance frequency coefficient (-7.1-7.2 ppm / DEG C), the preparation process is simple, the cost is low, the raw materials are non-toxic and easy to obtain, and the ceramic material is suitable for being used as an LTCC dielectric substrate material and has important industrial application value.

The invention discloses a low-dielectric-constant polyamide material, and relates to the technical field of high polymer materials. The invention discloses a low-dielectric-constant polyamide material. The composite material is prepared from the following raw materials in parts by weight: 35 to 45 parts of polyamide 66, 5 to 10 parts of polytetrafluoroethylene micro powder, 8 to 12 parts of modified porous siloxane microspheres, 3 to 7 parts of modified nano zinc oxide, 10 to 15 parts of glass fibers, 4 to 8 parts of polyether-ether-ketone, 1 to 3 parts of graphene nanosheets, 3 to 5 parts of fluororubber, 1 to 2 parts of a titanate coupling agent, 0.3 to 0.7 part of an antioxidant 1010, 0.5 to 1.0 part of ethylene bis stearamide and 0.1 to 0.3 part of an ultraviolet absorbent UV-531. The low-dielectric-constant polyamide material has the remarkable advantages that the raw materials are scientifically proportioned, and various modified components are contained to enhance the performance; all the components are subjected to special treatment, so that the compatibility is good; the preparation process is rigorous, and the material has excellent dielectric properties; and the material also has good heat resistance and weather resistance and strong mechanical properties, and is suitable for various scenes with high dielectric constant requirements.

The invention belongs to the field of microwave dielectric ceramic materials, and particularly provides a method for improving the performance of zinc aluminate microwave ceramic based on an LBSCA (Li2O-B2O3-SiO2-CaO-Al2O3) composite sintering aid, so that the prepared zinc aluminate microwave dielectric ceramic material has a low dielectric constant and a high thermal expansion coefficient, and is suitable for manufacturing a ceramic substrate with excellent performance. According to the invention, a Zn < 0.90 > Co < 0.10 > Al < 2 > O < 4 > system is adopted, an LBSCA (Li2O-B2O3-SiO2-CaO-Al2O3) composite sintering aid is introduced, and sintering and dielectric properties are optimized through a plurality of mechanisms. The doping of the LBSCA glass has obvious influence on the microstructure and density of the ceramic, and the microwave dielectric property of the ceramic is further improved. According to the invention, when the sintering temperature is 1175 DEG C and x is equal to 1.5 wt%, the optimal performance is as follows: epsilon r is equal to 5.25, Q * f is equal to 7334 GHz, and tauf is equal to-25.18 ppm / DEG C; the CTE value is the maximum value of 11.18 ppm / DEG C.

The invention relates to a high frequency cable coupler. Compact cable couplers connect cables with different wire gauges and do not interfere with electrical performance up to very high frequencies. Each cable coupler has a pair of conductive elements having first and second contact portions on opposite ends that terminate the wires of the first and second cables. A housing surrounds the conductive element, including a cable attachment. The conductive layer extends from the first cable to the second cable and is conformal with the underlying surface. The housing has a region having a lower dielectric constant adjacent the cable attachment. A parameter of the cable coupler in each of the plurality of portions may be selected to provide a matched impedance through the coupler. Such couplers enable dense connection of small diameter cables with connectors while large diameter cables provide low loss routing to remote locations to achieve high density signal connections with high signal integrity at frequencies sufficiently high to support 224 Gbp.

The invention provides hot-melt wave-absorbing resin, a low-frequency wave-absorbing prepreg and application of the hot-melt wave-absorbing resin and the low-frequency wave-absorbing prepreg in a low-broadband magnetic wave-absorbing composite material. The hot-melt wave-absorbing resin is prepared from the following raw materials: hot-melt resin and a composite absorbent, the composition comprises a combination of a coupling agent modified conductive absorbent and a magnetic absorbent. The raw materials of the low-frequency wave-absorbing prepreg comprise the hot-melt wave-absorbing resin and reinforced fibers with low dielectric constant and low gram weight. The hot-melt wave-absorbing resin provided by the invention realizes the low-frequency wave-absorbing performance covering 1GHz. Through the synergistic effect of the conductive absorbent and the magnetic absorbent, the broadband wave-absorbing prepreg covering low frequency is prepared by using a hot melting method, the dielectric loss of the wave-absorbing prepreg is improved, and the low-frequency wave-absorbing performance is enhanced. And the formula can be changed according to frequency band requirements to meet the wave absorbing requirements of different frequency bands (from 0.3 GHz to 18GHz). According to the low-broadband magnetic wave-absorbing composite material with the wave-absorbing honeycomb provided by the invention, the wave-absorbing bandwidth coverage is expanded by 1-18 GHz.

To provide a solid composition which achieves both a low dielectric constant and a low coefficient of linear expansion.SOLUTION: A solid composition contains a fluorine resin, and a fibrous anisotropic filler, where a reduction rate of a coefficient of linear expansion at 20°C to 200°C of the solid composition to a coefficient of linear expansion at 20°C to 200°C of the fluorine resin is 50% or more.SELECTED DRAWING: None

The invention relates to an electronic component material technology, and aims to provide an LTCC (Low Temperature Co-Fired Ceramic) material with low dielectric constant and low dielectric loss and a preparation method thereof. The LTCC material is prepared from zinc borosilicate glass and zinc borosilicate microcrystalline glass with different softening point ranges, a ceramic filler, silicate and a metal oxide through ball milling, mixing, modeling and sintering, and the material contains Zn2SiO4 with a devitrified phase. According to the invention, two kinds of zinc borosilicate glass with different softening points are adopted as cooling assistants, and a devitrified phase Zn2SiO4 is generated through reaction in the sintering process, so that the problem of large dielectric loss of a composite system caused by more glass phases can be effectively improved; by flexibly regulating and controlling the content of each component and the components of the auxiliary materials, the sintering characteristics of the glass internal component regulation and control material are optimized, and the success rate of matching and co-firing of the material and silver is further improved; meanwhile, the sintering window is relatively wide, so that good quality stability of the product is favorably kept; the dielectric loss of the composite system is reduced by doping the nucleating agent, and the volume shrinkage process of the material is regulated and controlled.

A thermally curable modified polymer having high frequency and low dielectric constant, a synthesis method therefor and a use thereof. The thermally curable modified polymer has a monomer structure as shown in the following formula I. The thermally curable modified polymer can be widely applied to the fields of high-frequency communications, microelectronics industry, aerospace and the like as a low-dielectric-constant matrix resin or packaging material.

The disclosure relates to a multi-layered laminate comprising multiple metal foil layers and multiple dielectric (insulating) layers. At least one of the insulating layers includes a copolymer containing diisoalkenylarene (DIAEA) and divinylarene (DVA) units, optionally combined with a filler and / or another dielectric polymer. Another insulating layer includes another dielectric polymer distinct from the DIAEA-DVA copolymer. At least one copolymer-containing insulating layer is positioned adjacent to a metal foil layer. This copolymer layer enhances thermal stability at elevated temperatures and provides improved electrical performance such as reduced dielectric constant (Dk) and dissipation factor (Df) along with excellent processability.

To provide a ceramic having a high coefficient of thermal expansion and a low dielectric constant.SOLUTION: 50.0 to 90.0 mass% of 2MgO and SiO2, a total of 8.0 mass% or more of one of 7.0 to 14.0 mass% of ZrO2 and 10.0 to 50.0 mass% of Al2O3 or both of 14.0 mass% or less of ZrO2 and 50.0 mass% or less of Al2O3, and 3.0 to 15.0 mass% of one or more selected from Y2O3, CaO, CeO2, and HfO2, wherein a crystalline structure of the is a cubic structure. ZrO2.SELECTED DRAWING: None

The invention provides a low-dielectric-constant material dielectric property prediction method and system based on machine learning, and the method comprises the steps: obtaining material data, and carrying out the preprocessing to obtain basic attributes; performing feature engineering to obtain a feature matrix; dividing the feature matrix into a data set and processing the data set; training the model to obtain an optimal model; and evaluating the optimal model, and serializing and storing the optimal model. The structure of a machine learning method combining specific feature engineering, training data noise enhancement, a sample weighting strategy and a random forest model solves the problem that an existing machine learning model accurately predicts a specific low dielectric constant (lt; and 5) the problems that the precision in the aspect of materials is insufficient and the efficiency of a traditional material screening method is low are solved, and the efficiency and accuracy of discovery of the low-dielectric-constant new materials and the robustness and generalization ability of prediction are improved.

The invention belongs to the technical field of battery cooling liquid, and particularly relates to new energy automobile power battery cooling liquid and a preparation method thereof. The new energy automobile power battery cooling liquid is prepared from the following raw materials in percentage by mass: 40 to 60 percent of dihydric alcohol, 0.2 to 3 percent of a corrosion inhibitor, 0.1 to 0.5 percent of an antioxidant, 0.1 to 0.5 percent of a pH regulator, 0.01 to 0.05 percent of an anti-foaming agent, 0.005 to 0.015 percent of a nano additive and the balance of ionized water, the nano additive comprises an ionic flaky nano mineral, nano palygorskite and nano diamond in a mass ratio of (3-5): (0.1-0.5): (0.1-0.5). The new energy automobile power battery cooling liquid has good low dielectric constant, high thermal conductivity and good storage stability.

The invention discloses a flame-retardant epoxy resin adhesive with a low dielectric constant and a low dielectric loss factor as well as a preparation method and application of the flame-retardant epoxy resin adhesive, and belongs to the technical field of electrical insulating materials. The method comprises the following steps: uniformly mixing and stirring epoxy resin and alicyclic epoxy resin to obtain an epoxy resin mixture; uniformly stirring liquid acid anhydride, a flame retardant, an epoxy active toughening agent and an accelerant to obtain an epoxy resin curing agent; and vacuumizing and uniformly stirring the epoxy resin mixture and the epoxy resin curing agent to obtain the flame-retardant epoxy resin adhesive with low dielectric constant and low dielectric loss factor. Dielectric loss of the epoxy resin mixture is reduced through polarity complementation, and molecular chain segment polarization is reduced through an alicyclic epoxy resin ring structure. And the flame retardant is dispersed into a uniform flame-retardant phase in liquid anhydride, so that the mechanical property is prevented from being reduced. A flexibilizer and anhydride are grafted to introduce a flexible chain segment, vacuum mixing is performed to eliminate an air gap, and after gradient curing, a low dielectric constant, a low dielectric loss factor and flame retardance are obtained.

The invention provides a low dielectric glass fiber material as well as a preparation method and application thereof, and the low dielectric glass fiber material comprises the following components in percentage by weight: 54 to 57 percent of SiO2, 12 to 15 percent of Al2O3, 16 to 24 percent of B2O3, 1 to 2.5 percent of CaO, 2 to 5 percent of MgO, 2 to 4 percent of ZnO, 0.4 to 2 percent of TiO2, 0.2 to 0.5 percent of ZrO2 and 1.2 to 3.4 percent of CeO2. The glass with low dielectric constant and low dielectric loss performance is obtained by introducing low-content cerium oxide into a glass fiber material, controlling the content of SiO2 in a high range, adjusting the content of B2O3 in a low range and reasonably controlling the content of several main components, and the problems that the chemical stability of the glass fiber is reduced after cerium oxide is added, and the glass has low dielectric loss performance are solved. The thermal expansion coefficient is increased, so that thermal stress mismatching and cracking are caused when the material is matched with other materials for use.

The invention belongs to the technical field of electronic materials, and relates to a low-dielectric resin glue solution for a high-frequency high-speed copper-clad plate as well as a preparation method and application thereof, and the low-dielectric resin glue solution for the high-frequency high-speed copper-clad plate comprises the following components in parts by weight: 100 parts of a resin component, 2-4 parts of a compatibilizer, 2.5-4.5 parts of a curing system, 0.6-1.3 parts of an initiator, 55-80 parts of a filler and 1.1-2.3 parts of an auxiliary agent. By introducing a ternary interpenetrating network of the polybutylbenzene resin, the polyimide and the allyl-terminated modified polyphenyl ether, a resin compounding system is optimized; the copper-clad plate with the comprehensive performance of ultralow dielectric constant, ultralow dielectric loss, high peel strength and low Z-axis thermal expansion coefficient is realized by adopting double-initiator gradient curing, filler compounding dispersion and low-dielectric glass fabric-HVLP copper foil synergistic interface treatment; the method is suitable for high-frequency scenes such as 5G communication base stations and millimeter wave radars.

The invention discloses a high-frequency signal detection device. The high-frequency signal detection device comprises a probe seat, a pair of grounding probes and at least one signal probe, wherein a pair of first mounting parts and at least one second mounting part are correspondingly arranged in the probe seat according to an element to be detected, the pair of first mounting parts are positioned on two outer sides of the second mounting part, and each grounding probe is mounted in each first mounting part and can capture at least one grounding signal after being in contact with the element to be detected. The signal probe is installed in the second installation part, and the signal probe has a design capable of reducing a dielectric constant, and can capture a high-frequency signal after being contacted with the element to be detected. Therefore, signal reflection loss caused by group reactance mismatching during application is reduced through the special design of the signal probe, so that the accuracy of bandwidth detection is improved.

The invention discloses an epoxy modified polyimide coating with both low dielectric constant and flame retardance, which is prepared by the following steps: by taking polyimide resin and epoxy resin as matrixes, constructing a semi-interpenetrating network structure, stably dispersing and fixing a novel phosphorus-nitrogen synergistic flame retardant in the network in a nanoscale, thereby obtaining the epoxy modified polyimide coating with low dielectric constant and flame retardance. According to the design, excellent heat resistance, low dielectric constant and corrosion resistance of polyimide and good adhesive force and manufacturability of epoxy resin are integrated, and the performance limitation of a single resin matrix is overcome. The flame retardant disclosed by the invention exerts a gas phase-condensed phase synergistic flame retardant mechanism in a combustion process, not only can capture free radicals in a gas phase, but also can promote formation of a compact carbon layer in a condensed phase, so that a coating has efficient and good flame retardant performance, and meanwhile, the problem that an additive flame retardant is difficult to disperse in a coating is solved. The coating disclosed by the invention has wide application prospects in the fields of electronic device packaging protection, steel structure fire prevention and corrosion prevention, new energy automobile battery compartment protection and the like.

The invention provides a laser chip and a preparation method thereof. The laser chip comprises a light emitting region and an electric absorption modulation region. The electric absorption modulation area comprises a substrate, an active layer, a waveguide layer and a modulation electrode. The waveguide layer comprises a ridge structure, a first ridge groove and a second ridge groove, wherein the first ridge groove and the second ridge groove are located on two sides of the ridge structure. A first filling medium is arranged in the first ridge groove, and a second filling medium is arranged in the second ridge groove. The first filling medium and the second filling medium are both low-dielectric-constant media. One end of the modulation electrode is arranged on the surface of the ridge structure, and the other end is arranged on the surface of the first filling medium, namely the first filling medium is arranged between the modulation electrode and the laser chip. In the invention, when the first ridge groove and the second ridge groove are respectively filled with the low dielectric constant medium, the parasitic capacitance introduced when the modulation electrode covers along the two sides of the ridge structure can be reduced, and the dielectric loss is reduced, so that the influence of parasitic parameters on the modulation bandwidth of the laser chip is reduced, and the modulation bandwidth of the laser chip is improved.

The invention relates to the technical field of glass, and particularly discloses low dielectric loss glass and a preparation method thereof, the low dielectric loss glass comprises the following components by weight: 65%-70% of SiO2, 6%-11% of B2O3, 10%-15% of CaF2 + MgF2, 5%-10% of Al2O3, 1%-3% of ZrO2, 1%-3% of Na2O, 1%-10% of RE2O3 and 0.1%-2% of Li2O. The low-dielectric-loss glass provided by the invention shows excellent electrical performance in high-frequency application, can effectively reduce signal loss, and is suitable for microwave communication equipment, a high-frequency circuit substrate, a radio frequency device (such as an antenna and a filter), a photoelectric integrated circuit and other application scenes requiring low dielectric constant and low dielectric loss under a high-frequency condition; the invention provides a new choice for research and development of high-performance electronic devices, and has a wide application prospect.

The invention discloses a low-temperature sintered microwave dielectric ceramic material and a preparation method thereof, and belongs to the technical field of electronic materials. The composite material comprises the following raw materials: CaCO3, SrCO3, Bi2O3 and B2O3. The preparation method comprises the following steps: burdening and weighing according to a stoichiometric ratio CaxSr1-xBi2B2O7 (x is more than 0.1 and less than 0.9), then carrying out ball milling and mixing, pre-sintering to obtain pre-sintered ceramic powder, adding an organic material to prepare stable slurry, carrying out tape casting to obtain a green body, and sintering to obtain the low-temperature sintered microwave dielectric ceramic material. The sintering temperature of the ceramic material is 700-800 DEG C, the dielectric constant range is 4-8, the loss value is less than 0.00002, and the ceramic material has low dielectric constant and ultrahigh quality factor. The problems that an existing low-temperature sintering microwave dielectric ceramic material is high in water absorption and high in material cost are solved. The microwave ceramic dielectric is applied to the technical field of electronic components requiring low dielectric constant and low loss value microwave ceramic dielectric.

The invention provides an electronic-grade hollow silicon dioxide microsphere as well as a preparation method and application thereof. The preparation method comprises the following steps: by taking synthesized hyperbranched polysiloxane with a side chain functional group structure as a precursor and a nonionic surfactant as a structure-directing agent, obtaining emulsion oil drops with different structures, adding alkali, and performing in-situ conversion to form a hollow silicon dioxide microsphere structure with high porosity; a shell layer with the characteristics of higher purity, higher density, adjustable thickness and the like is formed by a sol-gel in-situ shell layer deposition technology; the compact shell layer is added to prevent resin and a solvent from entering the microspheres, water adsorption in the microspheres is reduced, meanwhile, the flowability of the microspheres in the resin can be enhanced, and the excellent performance of the hollow silicon dioxide microspheres can be played to the maximum extent. The dielectric constant Dk (at) 10GHz is less than 1.7, and the dielectric loss Df (at) 10GHZ is less than 0.1%; the material can be used as a low-dielectric-constant material, a heat-insulating material, a density-reducing filler, an insulating material and other

The invention belongs to the technical field of copper-clad plate materials, and particularly relates to a low-dielectric low-loss resin composition and a product and a preparation method thereof. The low-dielectric low-loss resin composition comprises the following components in parts by weight: 30-70 parts of polyphenyl ether; 10 to 50 parts of modified bismaleimide; 30 to 70 parts of a poly (1, 2-butadiene styrene) copolymer; 5 to 20 parts of partially hydrogenated poly (1, 2-butadiene); 1-10 parts of a cross-linking agent; 40 to 300 parts of an inorganic filler; 10 to 50 parts of a flame retardant; and 1-5 parts of a catalyst. The low-dielectric and low-loss resin composition provided by the invention maintains a low dielectric constant and low dielectric loss and also has a low thermal expansion coefficient, and a product prepared from the resin composition can meet the processing and application requirements of high-density, miniaturized and high-frequency and high-speed electronic devices.

A polishing composition, includes an abrasive; a pH adjuster; a barrier film removal rate enhancer; a low-k removal rate inhibitor; an azole-containing corrosion inhibitor; and a ruthenium removal rate enhancer. A method of polishing a substrate includes the steps of: applying the polishing composition described herein to a surface of a substrate, wherein the surface comprises ruthenium or a hard mask material; and bringing a pad into contact with the surface of the substrate and moving the pad in relation to the substrate.

The invention relates to fluorine-free polyimide containing hydrophobic groups and a preparation method thereof, and belongs to the field of novel high-performance polyimide materials. The fluorine-free polyimide containing the hydrophobic group has a repeating unit structure shown in a general formula (I) and is obtained by polymerizing a fluorine-free diamine monomer containing the hydrophobic group and having a structure shown in a general formula (II) with specific diamine and dianhydride monomers. The fluorine-free polyimide containing the hydrophobic group has relatively low water absorption rate, has a low dielectric constant and a low loss factor at high frequency, has excellent solubility and thermal stability, can meet the performance requirements of a high-frequency and high-speed circuit on a substrate material, and has a wide application prospect. The material can be used as an excellent fluoride-free insulating base material in the fields of super-large-scale integrated circuits, photosensitive polyamideimide and the like.