A sensor is a detecting device that can sense the measured information and can transform the sensed information into an electrical signal or other required form of information output to meet the information transmission, processing, storage, and Requirements for display, recording and control.
Classified according to the manufacturing process:
Integrated sensors are fabricated using standard process technology for the production of silicon-based semiconductor integrated circuits. Part of the circuitry used to initially process the signal under test is also typically integrated on the same chip, such as the MEMS sensor now being developed.
The thin film sensor is formed by a film of a corresponding sensitive material deposited on a dielectric substrate (substrate). When a mixing process is used, part of the circuit can also be fabricated on this substrate.
The thick film sensor is made by coating a slurry of a corresponding material on a ceramic substrate, which is usually made of Al2O3, and then heat-treated to form a thick film.
Ceramic sensors are produced using standard ceramic processes or some variation thereof (sol, gel, etc.). After the appropriate preparatory operation is completed, the formed component is sintered at a high temperature.
There are many common characteristics between the two processes of thick film and ceramic sensors. In some respects, the thick film process can be considered as a variant of the ceramic process.
The selection of sensors is not only in terms of sensitivity, frequency response, linear range, stability and accuracy. The stability is closely related to the substrate material. The first few items mainly look at the manufacturing process. In terms of stability, then The most suitable non-ceramic circuit board for sensors. The stability of ceramic materials is quite good. As long as the manufacturing process technology can pass, ceramic circuit boards are definitely better than other PCBs.
The best manufacturing process for ceramic circuit boards is LAM technology, Laser Activation Metallization (LAM technology), which uses high-energy laser beams to ionize ceramics and metals to make them strong.
However, at present, domestic sensor manufacturers are mainly small and medium-sized. There are still many film processes in use, and FR-4 substrates are used. The service life is not long, the stability is poor, and in a slightly harsh environment, they directly strike. It takes a lot of effort to get the sensor to keep up with international standards.
The sensor still needs ceramic circuit board. It has been widely used in developed countries. China is not really technically constrained, and the replacement of sensor circuit boards depends on the major manufacturers, Goer, Dahua. To take the lead, manufacturers to carry out technological innovation, in order to become bigger and stronger, China‘s sensor industry can also catch up with the pace of the world.