Brief Introduction of thick film electronic paste
In the 21st century, electronic information technology is developing towards t0 miniaturization, high-integration, high-frequency, and multi-dimension. high power, miniaturization, lightweight, multi-function, eco-friendly and low cost become the development direction of new electronic components inevitably. Integrated circuit is the crystallization of modern electronic technology development achievements, mainly including thick film hybrid integrated circuit, thin film hybrid integrated circuit and semiconductor integrated circuit. It has its own advantages: semiconductor integrated circuit takes the lead in digital circuit, suitable for mass production; Thin film hybrid IC has obvious advantages in microwave and high frequency circuits, while thick film hybrid IC has irreplaceable advantages in high temperature, high voltage and high power circuits.
The thick film hybrid integrated circuit, referred to as thick film circuit or thick film hybrid circuit, refers to the circuit unit that meets certain functional requirements by making interconnect wires, resistors, capacitors, and inductors on the substrate through screen printing, firing and other processes. Due to its advantages of small size, high power, reliable performance, flexible design, low cost and high cost performance, thick film circuit ADAPTS to the requirements of the development trend, occupying more than 80% of the market share in the hybrid circuit industry, increasingly prominent dominance.
Thick film circuit as an important branch of integrated circuit, with the emergence of thick film electronic materials and thick film technology, with its development and development. Thick film electronic material is the material base of thick film circuit, including substrate and thick film electronic paste. Substrate is the carrier of thick film circuit, and its material properties have an important influence on the quality of thick film circuit. Thick film electronic paste is the core and key of thick film circuit, its quality is directly related to the performance of thick film components. As the basic material of thick film electronic paste, there are many classification methods for thick film electronic paste.
According to different uses, can be divided into resistance paste, conductor paste and medium paste three categories.
According to the type of substrate used, it can be divided into ceramic substrate paste, polymer substrate paste, glass substrate pastes and composite substrate electronic paste, etc. At present, ceramic substrate electronic paste is the most widely used, among which AI203 ceramic substrate resistance paste is the earliest developed, mature technology, the largest amount. AIN substrate and other new ceramic substrate electronic paste meet the development requirements of high-power thick film circuit, the application field is expanding, and the proportion of ceramic substrate electronic paste is increasing. Polymer substrate, the representative of the glass substrate and composite substrate electronic pastes respectively for the polyester and the polyimide substrate calcium, sodium, window glass substrate and the glaze metal insulation substrate electronic pastes, all is the broadening of the application of thick film circuit and developed a new type of electronic paste, respectively in low, medium and high temperature firing, due to their respective professional and irreplaceability, market share rising to expand.
According to the price of conductive phase, it can be divided into noble metal electronic paste and base metal electronic paste. The representative systems of noble metal resistance paste are silver electronic paste and nail electronic paste. Base metal electronic slurry is represented by two aluminum silicate resistance slurry. Although noble metal paste has high stability and reliability, high precision and long life and other outstanding advantages, in the electronic technology is in an absolute dominant position, but to reduce the cost, reduce the amount of precious metal, the use of base metal is the development direction of electronic paste.
According to different sintering systems, it can be divided into high temperature sintered electronic paste, medium temperature sintered electronic paste and low temperature drying electronic paste. The sintering system of resistive slurry has great influence on its properties. The establishment of sintering system is not only related to the composition of slurry, but also to the type of substrate. High temperature sintering electric slurry firing temperature is generally about 850℃.The firing temperature of medium temperature sintered electronic slurry is generally within the range of 500-700℃.Organic resin prepared series of electronic paste is a drying resistance paste, drying temperature is 120-250℃.
According to different uses, it can be divided into general electronic paste and special electronic paste. General electronic paste technology adaptability and compatibility, including high-performance electronic paste and chip electronic paste, widely used in high reliability integrated circuits, precision discrete components and chip resistance components. Special electronic paste mainly includes thermistor paste, surge resistance paste and high power electronic paste, respectively, used in a variety of thermal sensing control components, surge protection circuit and high power thick film components.