Aluminum nitride (AlN) is a new type of ceramic material with excellent comprehensive properties. It has excellent thermal conductivity, reliable electrical insulation, low dielectric constant and dielectric loss, non-toxic, and a coefficient of thermal expansion compatible with silicon. The series of excellent characteristics are considered to be the ideal materials for highly concentrated semiconductor substrates and electronic device Glass Ceramic Bars packaging.
The thermal conductivity of aluminum nitride is 5 to 10 times that of the traditional substrate material aluminum oxide, which is close to the thermal conductivity of beryllium oxide. The thermal conductivity of Al2O3 substrates is low, and the thermal expansion coefficient is not very compatible with Si. Although BeO has Excellent comprehensive performance, its higher production cost and highly toxic shortcomings limit its application and promotion. Compared with several other ceramic materials, aluminum nitride ceramics have excellent comprehensive properties and are very suitable for semiconductor substrates and structural packaging. The potential of materials in the electronics industry is huge.
Hard Precision Ceramic, advanced ceramics division is a leading supplier of ceramic materials. We supply aluminum nitride ceramics products with excellent specifications and competitive prices.
Aluminum nitride is a ceramic material with excellent Machinable Ceramic Flange overall performance, and its thermal conductivity is 7 times higher than Alumina ceramics. At the same time, it has low dielectric constant, excellent electrical properties compared with alumina, thermal expansion rate similar to silicon, high specific strength, low density, non-toxic and other characteristics. Because of the development of microelectronics technology, electronic components are concentrating on miniaturization, lightness, integration, high reliability, high-power output, etc. More complex devices have higher requirements for heat dissipation of substrates and encapsulation materials. This situation further promotes the flourishing development of the AIN ceramic substrate. The following article will introduce the process of AIN substrates from powder to forming to end application.
During the preparation of aluminum nitride powder, its purity, particle size, oxygen content, and other impurity content will be the impact factors on the subsequent thermal conductivity of the product, and subsequent sintering and forming processes, and are also key factors in the performance of the final product. AIN powder is synthesized by direct nitriding method, carbon thermal reduction method, self-propagating high-temperature synthesis method, chemical vapor deposition method, etc. As a professional manufacturer, our raw material preparation process usually chooses the carbon thermal reduction forming method, that is, the mixture of alumina powder and carbon powder is reduced to nitride in the flowing nitrogen at a high temperature (1400℃~1800℃) to form AIN powder.
1. Hot Pressure sintering: that is, sintering of ceramics under a certain pressure, you can simultaneously heat sintering and pressurized forming, to get fine grain, high relative density, and good mechanical properties of ceramics.
2. Pressure-less sintering: The general temperature range of atmospheric pressure sintering AIN ceramics is 1600-2000℃. Appropriately increasing the sintering temperature and extending the holding time, can improve the density of AIN ceramics, but the strength is relatively low.
3. Microwave sintering: Microwave sintering is also a rapid sintering method, the use of microwave interaction with the medium to generate a dielectric loss so that the overall heat.
4. Discharge plasma sintering: Integrating Machinable Glass Ceramic Bar plasma activation, hot pressing, resistance heating, and other technologies, it has the characteristics of fast sintering speed and uniform grain size, but the equipment cost is high, and the size of the processed workpiece is limited.
5. Self-propagation sintering: #AIN ceramic materials are prepared directly by self-propagation high-temperature synthesis reaction under ultra-high-pressure nitrogen. However, it is difficult to obtain high-density AlN ceramic substrates because the Aluminum Nitride in the raw material tends to melt under the high-temperature combustion reaction, which hinders the penetration of nitrogen into the billet.
To achieve dense sintering of #AlNCeramicSubstrate, reduce impurities and grain boundary phase content, simplify the process and reduce costs, the AlN ceramic sintering process requires three core elements: 1. selection of a suitable sintering process; 2. atmosphere control; and 3. addition of suitable sintering aids.