Chapter 1 Adaptability to Extreme Environments
1. Extreme Temperature Tolerance
The thermal conductivity of aluminum nitride (AlN) ceramic substrates is 170-230W/(m·K), and they can work stably in the range of -55℃ to 600^℃, with no cracking after 1,500 thermal cycles. Alumina (Al₂O₃) ceramic shells maintain structural stability at high temperatures and are suitable for hot end components of aircraft engines (such as turbine blades). Their temperature resistance is 400-500℃ higher than that of traditional high-temperature alloys.
2. Radiation and Corrosion Resistance
Ceramic materials (such as SiC/SiC composites) can maintain stable mechanical properties in strong radiation environments, and can resist neutron irradiation doses of up to 10²²n/cm². The corrosion rate of aluminum nitride ceramics in high-temperature sulfur-containing gas environments (>600℃) is <0.01mg/cm²/year, and the corrosion rate of alumina ceramics in concentrated sulfuric acid/NaOH solutions is <0.02mg/cm²/year.
3. High mechanical strength and impact resistance
Alumina ceramics have a compressive strength of 2,500MPa, and silicon nitride (Si₃N₄) ceramics have a fracture toughness KIC of 6.5MPa. They can withstand a 20kN cyclic load and are suitable for spacecraft structures (such as satellite reflector bases). The density of C/SiC composite materials is only 30% of that of steel, but the bending strength reaches 450MPa (@1,600℃).
4. Airtightness and anti-electromagnetic interference
The leakage rate of HTCC ceramic shell is < 1×10⁻⁸ Pa・m³/s, the moisture absorption rate is <0.02%, meeting the IP67 protection level, and the shielding effectiveness reaches 60 – 80 dB (@1GHz), ensuring the reliability of onboard electronic systems in vacuum and strong electromagnetic environments.
5. Lightweight and matching thermal expansion coefficient
The density of silicon nitride ceramics is 3.2g/cm³, which is only 40% of that of nickel-based high-temperature alloys. At the same time, the thermal expansion coefficient of 3.2×10-6℃ is highly matched with silicon chips (3×10-6℃), reducing the risk of thermal stress stratification.
Typical application cases:
Satellite electronic systems: HTCC ceramic shells integrate microwave circuits and optical couplers, and hermetic packaging ensures the long-term stability of chips in space radiation environments.
Hypersonic vehicle thermal protection: C/SiC composites are used for nose cones and wing leading edges, with a temperature resistance of 1,650℃ and an oxidation kinetic constant that is 50% lower than traditional materials.
Through material innovation (such as SiBN ceramic-based composites) and process optimization (such as HTCC multilayer co-firing), semiconductor ceramic technology provides a highly reliable solution for aerospace extreme environment applications.
Chapter 2 Lightweight and high-strength performance
1. Lightweight performance
The density of silicon nitride (Si₃N₄) ceramics is 3.2g/cm³, which is only 40% of steel, while the density of silicon carbide (SiC)-based composites is 2.5∼3.0 g/cm3, which is 30% of nickel-based high-temperature alloys. For example, Al₂O₃ fiber-reinforced Al₂O₃ composites (Al₂O3f/Al₂O3) have lower density than high-temperature alloys and higher temperature resistance by 400-500℃.
2. High strength and high temperature resistance
The bending strength of silicon nitride ceramics is >800MPa, and the fracture toughness KIC is 6.5MPa; the compressive strength of alumina (Al₂O₃) ceramics is 2,500MPa. Silicon carbide-based composite materials (C/SiC) still maintain a bending strength of 450MPa at 1,600^℃, which is suitable for thermal protection of hypersonic aircraft nose cones and wing leading edges.
3. Thermal expansion coefficient matching
The thermal expansion coefficient of aluminum nitride (AlN) substrate is 4.5×10-6℃, and that of silicon nitride (Si₃N₄) is 3.2×10-6℃, which is highly matched with silicon chips (3×10-6℃), reducing the risk of thermal stress delamination.
4. High temperature stability and corrosion resistance
The alumina ceramic shell remains structurally stable at 600^℃, and there is no cracking after 1,500 thermal cycles (-55^℃-150^℃); the corrosion rate of aluminum nitride ceramics in a high temperature (>600℃) environment containing sulfur gas is <0.01mg/cm2/year.
Typical application cases:
Satellite structural parts: Silicon nitride ceramic substrates are used for satellite reflector bases. The density is only 40% of steel, but the bending strength is >800MPa.
Hot end parts of aviation engines: C/SiC composite materials replace high-temperature alloys, with a temperature resistance of 1,650℃ and a 50% reduction in oxidation kinetic constants.
Through material innovation (such as ceramic-based composites) and process optimization (such as HTCC multilayer co-firing), semiconductor ceramic technology provides a comprehensive solution of lightweight and high strength for the aerospace field.
Chapter 3 Electromagnetic Compatibility (EMC) and Shielding Performance
1. High Frequency, Low Loss and Signal Integrity
The dielectric loss of alumina ceramics is <0.002, the dielectric constant is 9.8, and it supports 40Hz high-frequency signal transmission. It can reduce the attenuation rate of millimeter-wave signals from 1.2dB/mm of traditional substrates to 0.3dB/mm, significantly improving the beam pointing accuracy of phased array radars (up to 0.05.
2. Electromagnetic Shielding Effectiveness
The shielding effectiveness of HTCC ceramic shells is 60-80dB (@1GHz), and electromagnetic interference (EMI) isolation is achieved through multi-layer ceramic structure and metallization process. For example, the reflection and absorption efficiency of carbon nanotube-enhanced SiCN/YSZ composite ceramic materials in EMI shielding are comprehensively improved, which is suitable for electromagnetic protection of high-speed aircraft.
3. Airtightness and Environmental Isolation
The leakage rate of ceramic shells prepared by HTCC process is <1×10-8 Pa·m³/s, moisture absorption rate <0.02%, meets IP67 protection level, effectively isolates external electromagnetic interference and moisture penetration.
4. Thermal-electric collaborative design
The thermal conductivity of aluminum nitride (AlN) substrate is 170-230W/(m·K), and the thermal expansion coefficient is 4.5×10-6/℃. It matches the chip to reduce thermal stress, and realizes the coordinated optimization of electromagnetic compatibility and heat dissipation through three-dimensional wiring.
Typical applications:
Satellite communication system: CQFN ceramic shell integrates microwave circuit and optical coupler, with shielding effectiveness of 75dB (@10GHz) to ensure signal transmission stability.
Hypersonic aircraft: YSZ fiber reinforced SiCN ceramic composite material provides dual functions of EMI shielding and heat insulation, and the thermal conductivity is 22.5% lower than that of traditional materials.
Chapter 4 Corrosion resistance and oxidation resistance
1. High temperature oxidation resistance
Silicon carbide-based composite material (C/SiC):
In a high-temperature oxidizing environment (>1,200℃), a dense SiO₂ protective layer is generated on the surface, and the oxidation kinetic constant is as low as 1.2×10-3mg2/cm4/h, which is more than 50% lower than that of traditional high-temperature alloys (such as nickel-based alloys).
Application: Hypersonic vehicle nose cone and wing leading edge, temperature resistance up to 1,650℃, oxidation weight loss rate <0.5% (@1,500℃/100h).
Zirconia toughened ceramics (Y-TZP):
Through the phase transformation toughening mechanism (martensitic phase transformation), the bending strength is still maintained at >1,000MPa at high temperature (800℃), and the oxidation rate is <0.01 mg/cm²/h (@1,000℃).
Application: Rocket engine combustion chamber lining, resistant to high-temperature gas scouring.
2. Chemical corrosion resistance
Aluminum nitride (AlN) ceramics:
In corrosive gas environments containing sulfur, chlorine, etc. (such as aviation fuel combustion products), the corrosion rate is <0.005mg/cm²/year (@600℃), which is better than stainless steel (>0.1mg/cm2/year).
Application: Aviation engine sensor packaging, resistant to H₂S/SO₂ gas corrosion.
Alumina (Al₂O₃) ceramics:
The corrosion rate in strong acid (concentrated sulfuric acid) and strong alkali (NaOH solution) is <0.02mg/cm²/year, suitable for spacecraft propellant tank sealing structure.
Application: Liquid oxygen/liquid hydrogen fuel valve seals, liquid hydrogen permeability resistance <1×10-10Pa·m³/s.
3. Extreme environmental stability
Thermal cycling and thermal shock resistance:
Silicon nitride (Si₃N₄) ceramics have a thermal shock resistance temperature difference of 800^℃, and the strength retention rate is >90% after 500 thermal cycles (-55℃-1,200^℃).
Application: Satellite attitude control thruster nozzle, resistant to liquid oxygen/kerosene combustion impact.
Anti-particle scouring and ablation:
C/SiC composite material has a mass ablation rate of <0.02mm/s under high-speed particle scouring (>5km/s), which is 80% lower than that of graphite material.
Application: Reentry vehicle thermal protection system (TPS), resistant to aerodynamic heating and micrometeorite impact.
4. Surface modification technology enhancement
Anti-oxidation coating:
The SiC/Si₃N₄ gradient coating is used to reduce the oxidation weight loss rate of C/C composite material at 1,500℃ from 15% to 2% (@100h).
Application: Space shuttle thermal protection tile, with a lifespan extended to 50 mission cycles.
Corrosion-resistant metallization layer:
The Ta/W multilayer metallization layer is prepared by magnetron sputtering, with a salt spray corrosion resistance time of >5,000 hours (ASTM B117 standard) and a square resistance of <0.01Ω.
Application: Electronic packaging of satellites in marine environments, resistant to high humidity and high salt environments.
5. Typical application cases
Turbine blades of aircraft engines:
SiC fiber reinforced SiC-based composite materials (SiC/SiC) replace nickel-based alloys, with a temperature resistance of 300°C and an oxidation life of 10,000 hours.
Space station sensor carrier:
The surface erosion rate of AlN ceramic carrier under atomic oxygen (LEO environment) irradiation is <0.1μm/year, ensuring the long-term stability of the sensor.
Technical breakthrough direction
High entropy ceramics (HECs):
Such as (Hf₀.₂Zr₀.₂Ti₀.₂Nb₀.₂Ta₀.₂)C, the oxidation resistance temperature exceeds 2,000^℃, and the corrosion rate is <0.001mg/cm²/h.
Self-healing ceramic coating:
Based on the self-healing mechanism of borosilicate glass phase, the crack healing efficiency is >80%, which is used in reusable launch vehicles.
Through material component optimization (such as rare earth doping) and advanced coating technology, semiconductor ceramics have achieved a leapfrog improvement in performance in the extreme corrosion and oxidation environment of aerospace.
Chapter 5 High performance and low power consumption performance
1. High thermal conductivity and thermal management
The thermal conductivity of aluminum nitride (AlN) ceramic substrates is 170-230W/(m·K, and that of beryllium oxide (BeO) ceramics is as high as 330W/(m·K, which can control the chip junction temperature in a safe zone (such as reducing the probability of thermal failure of IGBT modules from 12% to 0.5%), significantly improving power density and reducing energy consumption. Silicon nitride (Si₃N₄) ceramic substrates achieve a thermal expansion coefficient of 3.2×10-6/℃ through the AMB process, which is highly matched with the chip, reducing the risk of thermal stress stratification and ensuring long-term stable operation of high-power devices.
2. High frequency, low loss and signal integrity
The dielectric loss of alumina (Al₂O₃) ceramic shell is <0.002, the dielectric constant is 9.8, and it supports 40GHz high-frequency signal transmission. The attenuation rate of millimeter-wave signals is reduced from 1.2dB/mm to 0.3dB/mm, which improves the beam pointing accuracy of phased array radar to 0.05 and reduces the power consumption of signal transmission. LTCC (low-temperature co-fired ceramic) technology realizes multi-layer 3D wiring to meet the compact design requirements of 5G RF modules and satellite communication equipment.
3. Lightweight and energy consumption optimization
The density of SiC/SiC ceramic-based composite materials is only 30% of that of nickel-based high-temperature alloys, and the temperature resistance is increased by 400-500℃. It can be applied to aircraft engine turbine blades to reduce the mass of aircraft and reduce fuel consumption. Al₂O3f/Al₂O3 composites replace high-temperature alloys to prepare helicopter tail nozzles, with a comprehensive weight reduction of 40%, which indirectly reduces system power consumption.
4. Low dielectric loss and energy efficiency
The line width/line spacing of the DPC (direct electroplating ceramic) substrate reaches 30μm, and the through-hole diameter is 60-120μm. Combined with the low dielectric loss characteristics (such as AlN ceramic dielectric loss <0.001), it reduces the switching loss by 15% in the automotive-grade IGBT module and improves the power conversion efficiency.
Typical application cases:
– Satellite communication system: CQFN ceramic shell integrated microwave circuit, shielding effectiveness 75dB (@10GHz), support 400Gb/s high-speed transmission, and power consumption is reduced by 20% compared with metal packaging.
– Hypersonic aircraft: AMB process silicon nitride substrate maintains a bending strength of 450MPa at 1,600^℃, and the thermal cycle life is increased to 5,000 times, reducing the energy consumption of the cooling system.
Chapter 6 Breakthrough Innovation Technology
1. Ultra-high thermal conductivity and thermal management capabilities
The thermal conductivity of aluminum nitride (AlN) ceramic substrate is 170-230W/(m·K, and the thermal expansion coefficient is 4.5×10-6/℃, which is highly matched with silicon chips. The chip junction temperature control accuracy can be improved to ±1°C, significantly reducing the probability of thermal failure (such as IGBT modules from 12% to 0.5%). The HTCC (high temperature co-fired ceramic) process realizes multi-layer 3D wiring and supports system-level packaging (SIP), which increases the chip integration by 3 times under the same area.
2. Extreme environment adaptability
The density of SiC fiber reinforced SiC-based composite materials (SiCf/SiC) is only 30% of that of nickel-based high-temperature alloys, and the temperature resistance is improved by 400-500℃ (up to 1,650℃), and the oxidation kinetic constant is reduced by 50%. C/SiC composite materials are used in hypersonic vehicle nose cones, and the mass ablation rate is <0.02mm/s (@5 km/s particle erosion), which is 80% lower than graphite.
3. High-frequency signals and electromagnetic compatibility
The dielectric loss of alumina (Al₂O₃) ceramic shell is <0.002, supporting 40GHz high-frequency transmission, and the attenuation rate of millimeter-wave signals is reduced from 1.2dB/mm to 0.3dB/mm. The shielding effectiveness of HTCC shell reaches 60-80dB (@1GHz), the leakage rate is <1×10-8Pa·m³/s, and it meets the IP67 protection level.
4. Lightweight and multifunctional integration
Al₂O3f/Al₂O3 composite replaces high-temperature alloy to prepare helicopter tail nozzle, with a comprehensive weight reduction of 40%. The thermal expansion coefficient of cordierite ceramic lens is <1×10-7/℃, which is used in satellite laser communication systems, and the dimensional accuracy stability is improved by 2 times. CQFN ceramic shell integrates microwave circuits and optical couplers, supports 400Gb/s transmission rate, and reduces power consumption by 20%.
5. Innovation in surface modification technology
The salt spray corrosion resistance time of magnetron sputtering Ta/W multilayer metallization layer is >5,000 hours (ASTM B117), and the square resistance is <0.01Ω. The SiC/Si₃N₄ gradient coating reduces the oxidation weight loss rate of C/C composite materials from 15% to 2% at 1,500℃.
Typical applications Breaking:
– Satellite reflector base: C/SiC composite material density is 2.5g/cm³, stiffness is 50% higher than traditional materials, and surface roughness is <1nm.
– Reusable rocket: self-repairing ceramic coating crack healing efficiency is >80%, supporting >50 mission cycles.
Chapter 7 Advanced Manufacturing and New Material Application Technology
1. System-level packaging (SIP) and high integration
The HTCC (high temperature co-fired ceramic) process achieves system-level packaging through multi-layer 3D wiring, and the chip integration is increased by 3 times under the same area. For example, CQFN ceramic shell integrates microwave circuits and optical couplers, supports 400Gb/s high-speed transmission, and power consumption is reduced by 20% compared with metal packaging.
2. Extreme environment adaptability
The density of SiC fiber reinforced SiC-based composite material (SiCf/SiC) is only 30% of that of nickel-based high-temperature alloy, the temperature resistance is increased by 400-500℃ (up to 1,650℃), and the oxidation kinetic constant is reduced by 50%. Al₂O3f/Al₂O3 composites replace high-temperature alloys to prepare helicopter tail nozzles, with a comprehensive weight reduction of 40%.
3. High-frequency signals and thermal management
The dielectric loss of alumina (Al₂O₃) ceramic shells is <0.002, supporting 40GHz high-frequency transmission, and the attenuation rate of millimeter-wave signals is reduced from 1.2dB/mm to 0.3dB/mm. The thermal conductivity of aluminum nitride (AlN) substrates is 170-230W/(m·K), and the thermal expansion coefficient is 4.5×10-6/℃. It matches the chip to reduce thermal stress, and the probability of thermal failure is reduced from 12% to 0.5%.
4. Lightweight and corrosion resistance
The bending strength of silicon nitride (Si₃N₄) ceramics is >800MPa, the fracture toughness KIC is 6.5MPa, and the thermal shock temperature difference is 800℃. The corrosion rate of AlN ceramics in sulfur-containing gas environments is <0.005mg/cm²/year, which is better than stainless steel.
5. Breakthroughs in new materials and processes
The oxidation resistance temperature of high-entropy ceramics (such as Hf-Zr-Ti-Nb-Ta carbides) exceeds 2,000^℃, and the corrosion rate is <0.001mg/cm²/h. The silicon nitride substrate prepared by the AMB (active metal brazing) process maintains a bending strength of 450MPa at 1,600^℃, and the thermal cycle life is increased to 5,000 times.
Typical applications:
– Satellite reflector base: C/SiC composite material density 2.5g/cm3, stiffness increased by 50%, surface roughness <1nm.
– Aircraft engine turbine blades: SiCf/SiC replaces nickel-based alloys, with a temperature resistance of 1,650℃ and an oxidation life extended to 10,000 hours.
