Study On The Dissolution Of Substrate And IMC Growth In The Interfacial Reaction Of Cu/Ga And Cu-Sn/Ga

With the development of electronic equipment,more and more attention has been paid for flexible electronic equipment.Flexible electronic devices have more stringent requirement on bending performance and portability of devices.Ga and Ga-based alloys have gained a lot of interest in the scientific literature because of their high electrical conductivity,high thermal conductivity,non-toxicity,and non-volatile properties,and ambient temperature liquid metal has become one of the alternatives for lightweight electronic interconnection.Ga and Ga-based alloys have gained a lot of recognition for their liquid-state applications as well as their ability as a bonding material in microelectronic assemblies.Most of the properties are due to their ability to form stable high melting temperature solid solutions and intermetallic compounds(IMC)with other metals,including copper,nickel,and aluminum.Another notable feature of gallium metal is its strong corrosiveness and reactivity with other metals.Liquid Ga has a high tendency to make interfacial reactions with substrates.This ability has given it an advantage over other metals for the past few years but still has a lot of things to discover in this area.In this present work,the interfacial reaction of the Cu/Ga and Cu-Sn/Ga interfaces under various service conditions are analyzed by keeping the temperature constant and regulating the reaction time.SEM,EPMA,and other analytical methods were used to describe the morphology,chemical composition,substrate dissolution,and IMC growth kinetics of the intermetallic compounds at the sample interface.The Cu/Ga interface reaction was carried out at 100?for 1,2,4,and 8 hours and at 150?for 0.5,1,3,and 6 h.The dissolution of Cu substrate and IMC formation increased with the increase of reaction time but the Cu dissolution rate and IMC growth rate were decreased with increasing reaction time.Further,the Cu/Sn interface reaction was carried out at 260?for 2 hours,followed by the reaction with liquid Ga for 1,2,4,and 8hours at 100?.Cu₃Sn layer acted as a barrier for the Cu substrate which suppress the dissolution of Cu substrate during the Cu-Sn/Ga reaction.After the entire consumption of Cu₃Sn layer,the dissolution rate rapidly increased.This study aims to enhance the understanding of Cu-Sn/Ga interfacial reactions at low temperatures for future use in the electronic industry and for the enhancement of flexible interconnections.