Printed circuit board silver paste with low silver content and preparation method thereof

Abstract

A printed circuit board silver paste with low silver content comprises the following raw materials by weight: 40-50 parts of 1-10-micron silver powder, 15-20 parts of silver-coated glass powder, 2-4 parts of nickel-coated copper powder, 1-2 parts of benzotriazole, 6-8 parts of glass powder, 1-3 parts of nano carbon, 7-10 parts of ethyl cellulose, 7-9 parts of butyl carbitol acetat, 1-2 parts of povidone, 1-2 parts of diisobutyl phthalate, 4-6 parts of ethanol, 3-5 parts of castor oil, and 5-8 parts of isobutanol. Through the use of silver-coated glass powder, nickel-coated copper powder and nano carbon, the electrical conductivity of the silver paste is improved, and the consumption of silver powder is reduced. Through the use of silver-coated glass powder, the wettability and surface smoothness of the paste are improved, and the cohesiveness is improved. Through the use of benzotriazole, metal powder is not easy to oxidize in the manufacturing process at high temperature, and good electrical conductivity is maintained. The production process of the silver paste is unique, and silver powder gathering and the influence thereof on the electrical conductivity can be prevented. The glass powder of the invention contains no lead, causes no pollution to the environment, and has low melting point and good cohesiveness.

Description

technical field [0001] The invention belongs to the technical field of electronic paste, and in particular relates to a silver paste for printed circuit boards with low silver content and a preparation method thereof. Background technique [0002] In the modern microelectronics industry, people have higher and higher requirements for electronic components, and the production is mostly carried out by process and standardization to reduce costs. The printed circuit board (PCB) was born to meet the needs of the microelectronics industry. Correspondingly, conduct research on new conductive pastes to match electronic pastes such as conductive pastes, electrode pastes, dielectric pastes, resistor pastes, and hole filling pastes with printed circuit boards (PCBs) that require new requirements. It is imperative. [0003] Generally speaking, the main components of electronic paste include functional phases such as metal, noble metal powder, etc., inorganic binders such as glass powd...

AI Technical Summary

Problems solved by technology

[0005] The binder in the conductive silver paste has a great influence on the yield of circuit printing, such as viscosity, cohesiveness, adhesion, leveling, film formation, solvent volatility, etc. will affect the printing performance of the circuit , there are pores, open circuits, etc., and sometimes the glass phase has not yet begun to melt after the organic matter has volatilized, resulting in the phenomenon that the conductive line falls off from the substrate, and the conductive line is scrapped. Therefore, the performance of the organic binder needs to be improved.

[0006] At present, many inorganic binders use glass powder. Glass powder is made of metal oxides, silicon oxide and other materials. If the melting point is too high, the glass phase has not yet started to melt after the volatilization of organic matter is completed, resulting in conductive lines obtained from conductive silver paste. The phenomenon of falling off from the substrate makes the conductive circuit scrapped; and many of the current glass powders contain harmful substances such as lead, which is not good for the environment, so it is necessary to develop glass powders with better performance