At present, the fifth-generation mobile communication technology (5G) is making great strides, and mankind will open a new era of extensive interconnection of everything and deep interaction between man and machine. In March 2020, the "Notice of the Ministry of Industry and Information Technology on Promoting the Accelerated Development of 5G" issued by the Ministry of Industry and Information Technology emphasized the need to "speed up 5G network construction and deployment, increase base station site resource support, and strengthen power and frequency guarantees." In the 5G era, smart terminals need to receive multiple frequency bands (5G/4G/3G/2G) and also process signals such as WIFI/GPS. Multiple filters need to be used in the transceiver link to avoid signal interference. The radio frequency filter can select and control the signal frequency in the communication link in the communication system, and filter out the out-of-band interference and noise.
Aluminum nitride, as a piezoelectric material for radio frequency filters, has shown good growth in demand. Aluminum nitride has the advantages of high thermal conductivity, high temperature insulation, good dielectric properties, high material strength at high temperatures, and low thermal expansion coefficient. AlN has two applications in RF filters. One of them is as a high-temperature heat-resistant ceramic used as a substrate for radio frequency filters. The production of aluminum nitride ceramic substrates is UNIPRETEC's area of expertise. AlN has high thermal conductivity, more than 5 times higher than alumina ceramics, and its expansion coefficient is low, which is consistent with the performance of silicon. The substrate made of aluminum nitride ceramics as the main raw material has the characteristics of high thermal conductivity, low expansion coefficient, high strength, and corrosion resistance. It is an ideal heat dissipation substrate and packaging material.
