The Two Amines Mixed With Copper Of Formate-based Granular Conductive Ink

Microelectronics technology is widely used in industrial production,defense and military fields.Printing electronics as one of the important technologies is gradually replacing the traditional manufacturing technology.Compared with traditional manufacturing technology,printed electronics has the advantages of simple method,low cost and green environment protection.Among the many printing technologies used in printing electronics,ink-jet printing is widely used because of its advantages such as no printing plate,low power consumption,flexible substrate,etc.It can spray the configured functional ink to the target position accurately,and form a film pattern or target device after curing at high temperature.The research on functional inks,especially conductive inks,is the key to the development of microelectronic manufacturing technology.At present,silver-based conductive inks have been widely used in thin film transistors,rf inductors and sensors to manufacture metal interconnects.However,due to the phenomenon of electromigration and high price of silver interconnection,its large-scale application is restricted.Therefore,the best alternative to silver-based ink is copper-based conductive ink.In the research of copper conductive ink,copper-based non-particle conductive ink has been widely concerned because of its high stability and low heat treatment temperature.In this paper,copper formate tetrahydrate was used as a metal precursor and1,2-Diaminopropane,isopropylamine,n-butylamine,octylamine,ethanolamine,N,N-DMEA,3-(diethyl amino)-1,2-propylene glycol were used as complexing agent to formulate seven copper formate tetrahydrate based non-particle type conductive ink through the liquid phase mixing method.Through the analysis of experimental data,it is found that complexing agent has important influence on the stability of conductive ink,heat treatment temperature,surface morphology and resistivity of conductive film formed after heat treatment.In most of the non-particle conductive inks currently studied,the heat treatment of inks requires shielding gas to isolate oxygen to prevent the oxidation of copper particles.The use of protective gas is unfavorable to the reduction of the cost of inkjet printing equipment,and the equipment's sealing requirements are also high,so it is difficult to ensure the safety of operation.The purpose of this project is to study a kind of copper-based non-particle conductive inkwhich can be heat treated in the air to form a film.Through the experimental analysis,We found that the conductive ink with 1,2-propylene diamine and 3-(diethyl amino)-1,2-propylene glycol as complexing agent has good stability and low resistivity.Among them,the copper conductive ink use 1,2-Diaminopropane as complexing agent shows the lowest resistivity about 9.27??·cm.The disadvantage is that due to the influence of anti-wetting and the generation of bubbles,the conductive film has formed a thin surface morphology with thick middle edge.The similar phenomenon does not exist in the conducting film with alcohol amine as complexing agent.In order to further optimize the surface morphology of the conductive film,Five kinds of conductive inks of different proportions were prepared by mixing1,2-Diaminopropane and 3-(diethyl amino)-1,2-propylene glycol as complexing agent.Through experimental analysis,adding 3-(diethyl amino)-1,2-propanediol to1,2-propylene diamine can solve the anti-wetting problem,The 3-(diethyl amino)-1,2-propanediol which has not been completely thermally decomposed can form a protective film to block oxygen and further prevent the oxidation of copper particles.At the same time,the increase of contact resistance effect is not obvious.The optimal molar ratio of 1,2-Diaminopropane and 3-(diethyl amino)-1,2-propanediol was determined to be 4:1.After 170? heat treatment 50 min,you can get the resistivity of 10.5??·cm copper conductive films.In addition,this paper also studied the effect of different heat treatment equipment on the resistivity of conductive film.After improved heating equipment,the resistivity of conductive film was reduced.Conductive film was prepared on the flexible substrate,170?/50 min heat treatment conditions,film resistivity as 15.9??cm,on a flexible substrate adhesion level 0B,mechanical stability is poor.In order to further optimize the adhesion of conductive films,PVP was added as binder on the basis of the improved conductive ink in chapter2.Experimental results show that the optimal PVP content of 1%,the resistivity of conductive films increased to 26.8??cm,adhesion level 3B,Mechanical stability is also enhanced.