A kind of conductive silver paste of phosphorus-containing copper alloy circuit board and preparation method thereof

Abstract

A phosphoric copper alloy circuit board conductive silver paste is made of the following raw materials: by weight, 20-30 parts of nano silver powder, 13-17 parts of cellulose acetate, 3-5 parts of expanded graphite powder, 40-50 parts of phosphoric copper alloy powder containing 2-4% of phosphorus, 9-12 parts of glass powder, 11-13 parts of ethyl acetate, 0.2-0.4 parts of alkyl polyglucoside, 2-3 parts of amyl acetate, 3-4 parts of butyl carbitol, 1-2 parts of sodium citrate, 2-4 parts of dimethyl formamide, 1-2 parts of polypropylene oxide glycol, and 0.4-0.7 parts of calcium lignosulphonate. The silver paste of the invention adopts phosphor-copper alloy powder, and the use amount of silver powder is saved; good conductive performance is ensured due to the use of nano silver powder; through the use of solvents of different boiling points and volatile speeds, the silver paste is enabled to gradually volatilize in the processes of printing, leveling and drying, pores, cracks and other defects are not easy to form, the silver paste and a printed circuit board can be firmly connected, and the connection strength is improved; and through the use of sodium citrate, metal powder is not easy to oxidize and can keep good conductivity during high-temperature processing.

Description

technical field [0001] The invention belongs to the technical field of electronic paste, in particular to a conductive silver paste for a phosphorus-containing copper alloy circuit board 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 p...

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