Infrared heating application - silver paste sintering process
The sintering process of silver paste includes: softening of glass powder, infiltration of silver powder and silicon substrate by glass liquid, rearrangement of silver powder particles driven by glass liquid, liquid phase solidification and shrinkage, etc., which may also include melting of silver powder and silicon, and recrystallization of silver powder particles.
High temperature sintered silver paste is a kind of conductive paste sintered at high temperature, and the sintering temperature can be sintered from 500 degree to 850 degree . It has the characteristics of low resistance, strong adhesion, good solderability and good printability. Typical applications are: solar cells, chip inductor end paste, automotive glass demisting line silver paste, conductive coating glass silver paste, quartz tube silver paste, GPS ceramic antenna silver paste, etc.
The higher the sintering temperature, the lower the viscosity of the molten glass, the better the fluidity, and the better the effect of infiltrating the silver powder and the matrix and driving the rearrangement of the silver powder. Between the silver layer and the substrate, it affects the conductivity of the silver film and the adhesion between the silver film and the substrate.
The sintering process of the silver paste has a great influence on the performance of the formed silver film, and the appropriate sintering temperature and holding time are beneficial to the formation of a conductive silver film with low square resistance and high adhesion.
Compared with the traditional heating method, the infrared heating method has the advantages of concentrated energy density and high thermal efficiency. Compared with the traditional heating source, the directional heating is strong. It does not need to heat the entire cavity and directly heats the object that needs to be heated. Direct radiant heating, in other words, is more efficient and energy-saving, with simple installation and easy temperature control, and is suitable for heating processes that require relatively high sintering temperature.
