Material Overview
Aluminum Nitride (AlN) is a cutting-edge ceramic material renowned for its exceptional thermal conductivity (up to 170 W/mK), low thermal expansion coefficient (4.6×10⁻⁶/K), and superior electrical insulation (resistivity >10¹⁶ Ω·m). Composed of aluminum and nitrogen, this non-oxide ceramic features a hexagonal wurtzite crystal structure, making it ideal for high-power electronics, aerospace components, and advanced semiconductor packaging.
Technical Data Table
| Property | AlN (99% Purity) | AlN (Composite) |
|---|---|---|
| Thermal Conductivity | 170–220 W/mK | 150–200 W/mK |
| Flexural Strength | 300–350 MPa | 400–450 MPa |
| Dielectric Constant | 8.8 (1 MHz) | 8.5–9.0 (1 MHz) |
| Max. Operating Temp. | 1,400°C | 1,200°C |
Key Features
- Ultra-High Thermal Conductivity: 10–15x higher than alumina (Al₂O₃), enabling efficient heat dissipation in high-power devices.
- Thermal Expansion Matching Silicon: Minimizes interfacial stress in electronic packaging, enhancing device reliability.
- Chemical Resistance: Resists acids, alkalis, and molten metals, suitable for harsh environments.
- Non-Toxic: Safer alternative to beryllium oxide (BeO), aligning with environmental regulations.
Applications
- Electronics: Substrates for high-frequency circuits, LED packaging, and power modules.
- Aerospace: Radomes, thermal management systems, and engine sensors.
- Semiconductors: Dielectric isolation layers and heat sinks for ICs.
- Industrial: Crucibles for molten metal handling and high-temperature furnace components.
Manufacturing & Customization
- Sintering Methods: Includes pressureless sintering (cost-effective), spark plasma sintering (high density), and microwave sintering (rapid processing).
- Advanced Machining: Laser cutting, magnetorheological polishing (MRF), and electrolytic in-process dressing (ELID) for micron-level precision.
- Composite Enhancements: Adding SiC or Y₂O₃ improves fracture toughness (up to 4.5 MPa√m) for demanding applications.
Aluminum nitride outperforms alumina due to its 6x higher thermal conductivity (170 W/mK vs. 30 W/mK for alumina), enabling efficient heat dissipation in high-density circuits. Its thermal expansion coefficient (4.6×10⁻⁶/K) closely matches silicon (3×10⁻⁶/K), reducing stress-induced failures in semiconductor packaging. Additionally, AlN’s non-toxicity and electrical insulation (>10¹⁶ Ω·m) make it safer and more reliable for power modules and LED systems.
AlN’s low dielectric loss (tanδ <0.0002 at 1 GHz) and high thermal stability minimize signal attenuation in high-frequency 5G circuits. Its ability to dissipate heat efficiently prevents overheating in RF amplifiers, improving signal integrity and device lifespan. For instance, AlN substrates in GaN-based RF devices reduce junction temperatures by 20%, enhancing power output by 15%.
Yes. AlN’s non-porous structure and chemical inertness allow it to withstand corrosive agents like sulfuric acid (pH <1) and molten aluminum. In chemical reactors, AlN thermocouple tubes show <0.1% weight loss after 5 years of exposure. Its resistance to oxidation at 1,400°C also makes it ideal for aerospace engine components.
To overcome brittleness, manufacturers use composite ceramics (e.g., AlN-SiC or AlN-Y₂O₃), boosting fracture toughness by 30%. Advanced sintering techniques like hot isostatic pressing (HIP) reduce porosity, enhancing mechanical strength (flexural strength up to 400 MPa). Additionally, plasma-assisted polishing (PAP) achieves mirror finishes (Ra <0.01 µm), critical for laser optics and precision sensors.