The construction of intermetallic compounds(IMCs)connection layers with special compositions by adding small amounts of alloying elements has been proven to be an effective strategy for improving the reliability of el...The construction of intermetallic compounds(IMCs)connection layers with special compositions by adding small amounts of alloying elements has been proven to be an effective strategy for improving the reliability of electronic component interconnect.However,the synergistic effect mechanism of multi-component alloy compositions on the growth behavior of IMCs is not clear.Herein,we successfully prepared a new quaternary alloy solder with a composition of Sn-0.7Cu-0.175Pt-0.025Al(wt%)using the high-throughput screening(HTS)method.The results showed that it possesses excellent welding performance with an inhibition rate over 40%on the growth of IMCs layers.For Cu_(6)Sn_(5),the co-doping of Al and Pt not only greatly improves its thermodynamic stability,but also effectively suppresses the phase transition.Meanwhile,the co-doping of Al and Pt also significantly delays the generation time of Kirkendall defects.The substitution sites of Al and Pt in Cu_(6)Sn_(5)have been explored using atomic resolution imaging and advanced data informatics,indicating that Al and Pt preferentially substitute Sn and Cu atoms,respectively,to generate(Cu,Pt)_(6)(Sn,Al)_(5).A one-dimensional(1D)kinetic model of the IMCs layer growth at the Sn solder/Cu substrate interface was derived and validated,and the results showed that the error of the derived mathematical model is less than 5%.Finally,the synergistic mechanism of Al and Pt co-doping on the growth rate of Cu_(6)Sn_(5)was further elucidated.This work provides a feasible route for the design and development of multi-component alloy solders.展开更多
The wetting behavior of liquid tin(Sn)solder on copper(Cu)substrate at 250℃was investigated by the wetting balance method under the action of direct current(DC).The curves of wetting balance were measured and the mor...The wetting behavior of liquid tin(Sn)solder on copper(Cu)substrate at 250℃was investigated by the wetting balance method under the action of direct current(DC).The curves of wetting balance were measured and the morphology of the intermetallic compound(IMC)precipitated at the interface were observed.Results show that DC has a significant effect on the wettability and IMC.As the current increases,the balance wetting force and the thickness of the IMC layer increase.The direction of the DC also has a certain effect on the balance wetting force and IMC layer.When the current is negative,the final balance wetting force and the thickness of the Cu_(6)Sn_(5) layer are significantly higher than those in the positive current case,which is attributed to electromigration.The IMC precipitation at the interface provides a chemical driving force for the movement of the triple junction.The interaction of the interface atoms and the chemical reaction are enhanced by DC,thereby improving wettability.Meanwhile,the Marangoni convection caused by DC inside liquid Sn solder changes the structure of triple junction,which provides a physical driving force for the spread of the liquid Sn solder on the Cu substrate.展开更多
基金financially supported by the Innovation Team Cultivation Project of Yunnan Province(No.202005AE160016)the Key Research&Development Program of Yunnan Province(No.202103AA080017)Yunnan Ten Thousand Talents Plan Young&Elite Talents Project(No.YNWR-QNBJ2018-044)。
文摘The construction of intermetallic compounds(IMCs)connection layers with special compositions by adding small amounts of alloying elements has been proven to be an effective strategy for improving the reliability of electronic component interconnect.However,the synergistic effect mechanism of multi-component alloy compositions on the growth behavior of IMCs is not clear.Herein,we successfully prepared a new quaternary alloy solder with a composition of Sn-0.7Cu-0.175Pt-0.025Al(wt%)using the high-throughput screening(HTS)method.The results showed that it possesses excellent welding performance with an inhibition rate over 40%on the growth of IMCs layers.For Cu_(6)Sn_(5),the co-doping of Al and Pt not only greatly improves its thermodynamic stability,but also effectively suppresses the phase transition.Meanwhile,the co-doping of Al and Pt also significantly delays the generation time of Kirkendall defects.The substitution sites of Al and Pt in Cu_(6)Sn_(5)have been explored using atomic resolution imaging and advanced data informatics,indicating that Al and Pt preferentially substitute Sn and Cu atoms,respectively,to generate(Cu,Pt)_(6)(Sn,Al)_(5).A one-dimensional(1D)kinetic model of the IMCs layer growth at the Sn solder/Cu substrate interface was derived and validated,and the results showed that the error of the derived mathematical model is less than 5%.Finally,the synergistic mechanism of Al and Pt co-doping on the growth rate of Cu_(6)Sn_(5)was further elucidated.This work provides a feasible route for the design and development of multi-component alloy solders.
基金Doctoral Research Start-up Fund of Lanzhou University of Arts and Science(2021-9)Innovation Fund for Colleges and Universities of Gansu Province,China(2022B-265)。
文摘The wetting behavior of liquid tin(Sn)solder on copper(Cu)substrate at 250℃was investigated by the wetting balance method under the action of direct current(DC).The curves of wetting balance were measured and the morphology of the intermetallic compound(IMC)precipitated at the interface were observed.Results show that DC has a significant effect on the wettability and IMC.As the current increases,the balance wetting force and the thickness of the IMC layer increase.The direction of the DC also has a certain effect on the balance wetting force and IMC layer.When the current is negative,the final balance wetting force and the thickness of the Cu_(6)Sn_(5) layer are significantly higher than those in the positive current case,which is attributed to electromigration.The IMC precipitation at the interface provides a chemical driving force for the movement of the triple junction.The interaction of the interface atoms and the chemical reaction are enhanced by DC,thereby improving wettability.Meanwhile,the Marangoni convection caused by DC inside liquid Sn solder changes the structure of triple junction,which provides a physical driving force for the spread of the liquid Sn solder on the Cu substrate.
