Now showing 1 - 10 of 13
  • Publication
    Suppression of (Cu,Ni)6Sn5 Intermetallic Compound in Sn-0.7Cu-0.05Ni+1wt.TiO2 Solder Paste Composite Subjected to Isothermal Aging
    ( 2020-03-18)
    Mohd Said R.
    ;
    ;
    Salleh M.M.
    ;
    This paper investigated the intermetallic compound (IMC) layer that formed in Sn-0.7Cu-0.05Ni+1wt.% TiO2 (SCNT) composite solder paste added with reinforcement (TiO2) particles. Besides, the growth of the IMC layer during subsequent aging at temperature of 75 °C, 125 °C and 150 °C also being studied. Scanning electron microscopy was used to observe the IMC growth and to measure the thickness of IMC layer. The interfacial IMC layer has been suppressed whereas the activation energy value of the composite solder paste was high (37.35 kJ/mol) which in turn improved the thermal stability of the IMC layer. Results also show the IMC formed at bulk solder microstructure of SCNT solder paste composite was refined. The presence of TiO2 particles has become the obstacle for the Cu atom diffusion from the substrate to the solder and Sn atom from the solder, thus, successful for the suppression of the IMC layer.
  • Publication
    Microstructure and growth kinetic study in Sn–Cu transient liquid phase sintering solder paste
    (Springer, 2020) ;
    Mohammad Zikry Ramli
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    ;
    H. Yasuda
    ;
    ;
    K. Nogita
    The feasibility of the highly reliable and replicable microstructure formation of the transient liquid phase sintering (TLPS) paste during the early soldering and isothermal aging on the Cu substrate had been successfully investigated in this study. By using the Sn–0.7 wt% Cu (SC) solder paste as the base material and the Cu particles in the production of the TLPS Sn–10 wt% Cu (SC10) solder paste, the ensuing Cu6Sn5 phase from the isothermal aging process was found to have reduced the β-Sn area of the bulk SC10 solder microstructure. The growth kinetic for TLPS SC10 resulted in a 26.76 kJ/mol of activation energy level. The real-time synchrotron radiation imaging technique that was employed in studying the growth and formation of the primary intermetallic phases at the solder joints had also discovered the primary intermetallic in TLPS SC10 was not only found to have experienced an early nucleation just after the solder had melted, but its growth was also restricted prior to the solidification of the liquid solder. Therefore, the relevance of the results that were obtained from this research may offer a possible solution for aiding the future development of highly reliable solder joints in high temperature solder applications.
  • Publication
    The effect of Nickel addition on lead-free solder for high power module devices - short review
    (Springer, 2023)
    Chong Meng Low
    ;
    The issue of substituting high lead (Pb) solders in elevated temperature applications such as in high power module devices has been a major concern due to the potential toxicity of lead (Pb) to the environment and human health. A significant increase in health and environmental awareness has paved the way for the development of lead-free solder in the elevated temperature applications. The alloying element plays an important role in Pb-free solder as it relates to the reliability of bonding, as well as the mechanical, thermal and electrical properties of solder joint. The addition of nickel (Ni) tends to enhance the microstructure of the solder and the formation of intermetallic compounds, as well as the properties of the solder joints, yet the experimental data on the effect of the addition of nickel on the high temperature applications is not established and still open for discussion. In this paper, a review on recent research on the effect of nickel addition on the high temperature applications such as in high power module devices is studied.
  • Publication
    Superconducting lead-free solder joint: a short review
    (IOP Publishing, 2020) ; ; ;
    Mohd Izrul Izwan Ramli
    Superconducting solders are widely used as joining material to connect superconducting wires such as Niobium-titanium (NbTi) and Niobium-tin (Nb3Sn) wires in commercial superconducting magnet applications. The physical and superconducting properties of the solder materials are very important since it influence the overall performance of the joint during service. Pb-Bi solder alloy widely used due to their good properties suitable for the superconducting application, however, the restriction on the use of Pb in industry lead to the development of new Pb-free solder material. This paper reviews the superconducting Pb-free solder alternatives, including In-Sn based solder. Besides that, the effect of bismuth (Bi) and antimony (Sb) addition to the binary In-Sn solder alloy were also discussed.
      3  20
  • Publication
    The effect of thermal annealing on the microstructure and mechanical properties of Sn-0.7Cu-xZn solder joint
    The microstructural properties of a Pb-free solder joint significantly affect its mechanical behaviours. This paper details a systematic study of the effect of the annealing process on the microstructure and shear strength of a Zn-added Sn-0.7Cu solder joint. The results indicated that the IMC layer’s thickness at the solder/Cu interface increases with annealing time. The interfacial IMC layer of the Sn-0.7Cu solder joint gradually thickened with increasing annealing time and annealing temperature, while the interfacial IMC layer’s morphology changed from scallop-type to layer-type after the annealing process. However, the addition of 1.0 wt.% and 1.5 wt.% Zn in the Sn-0.7Cu effectively altered the interfacial IMC phase to Cu-Zn and suppressed the growth of Cu3Sn during the annealing process. The single-lap shear tests results confirmed that the addition of Zn decreased the shear strength of Sn-0.7Cu. The interfacial IMC of the Cu6Sn5 phase in Sn-0.7Cu changed to Cu-Zn due to the addition of Zn. The shear fractures in the annealed solder joint were ductile within the bulk solder instead of the interfacial IMC layer. Increased annealing time resulted in the increased presence of the Cu-Zn phase, which decreased the hardness and shear strength of the Sn-0.7Cu solder joint.
      2  19
  • Publication
    The effect of thermal annealing on the microstructure and mechanical properties of Sn-0.7Cu-xZn Solder Joint
    The microstructural properties of a Pb-free solder joint significantly affect its mechanical behaviours. This paper details a systematic study of the effect of the annealing process on the microstructure and shear strength of a Zn-added Sn-0.7Cu solder joint. The results indicated that the IMC layer’s thickness at the solder/Cu interface increases with annealing time. The interfacial IMC layer of the Sn-0.7Cu solder joint gradually thickened with increasing annealing time and annealing temperature, while the interfacial IMC layer’s morphology changed from scallop-type to layer-type after the annealing process. However, the addition of 1.0 wt.% and 1.5 wt.% Zn in the Sn-0.7Cu effectively altered the interfacial IMC phase to Cu-Zn and suppressed the growth of Cu3Sn during the annealing process. The single-lap shear tests results confirmed that the addition of Zn decreased the shear strength of Sn-0.7Cu. The interfacial IMC of the Cu6Sn5 phase in Sn-0.7Cu changed to Cu-Zn due to the addition of Zn. The shear fractures in the annealed solder joint were ductile within the bulk solder instead of the interfacial IMC layer. Increased annealing time resulted in the increased presence of the Cu-Zn phase, which decreased the hardness and shear strength of the Sn-0.7Cu solder joint.
      3  15
  • Publication
    Performance of Sn-3.0Ag-0.5Cu composite solder with kaolin geopolymer ceramic reinforcement on microstructure and mechanical properties under isothermal ageing
    ( 2021)
    Nur Syahirah Mohamad Zaimi
    ;
    ;
    Andrei Victor Sandu
    ;
    ; ; ;
    Petrica Vizureanu
    ;
    ;
    Mohd Izrul Izwan Ramli
    This paper elucidates the effect of isothermal ageing at temperature of 85 °C, 125 °C and 150 °C for 100, 500 and 1000 h on Sn-3.0Ag-0.5Cu (SAC305) lead-free solder with the addition of 1 wt% kaolin geopolymer ceramic (KGC) reinforcement particles. SAC305-KGC composite solders were fabricated through powder metallurgy using a hybrid microwave sintering method and reflowed on copper substrate printed circuit board with an organic solderability preservative surface finish. The results revealed that, the addition of KGC was beneficial in improving the total thickness of interfacial intermetallic compound (IMC) layer. At higher isothermal ageing of 150 °C and 1000 h, the IMC layer in SAC305-KGC composite solder was towards a planar-type morphology. Moreover, the growth of total interfacial IMC layer and Cu3Sn layer during isothermal ageing was found to be controlled by bulk diffusion and grain-boundary process, respectively. The activation energy possessed by SAC305-KGC composite solder for total interfacial IMC layer and Cu3Sn IMC was 74 kJ/mol and 104 kJ/mol, respectively. Based on a lap shear test, the shear strength of SAC305-KGC composite solder exhibited higher shear strength than non-reinforced SAC305 solder. Meanwhile, the solder joints failure mode after shear testing was a combination of brittle and ductile modes at higher ageing temperature and time for SAC305-KGC composite solder.
      2  10
  • Publication
    The study of interfacial reaction between SnAgCu (SAC) lead-free solder alloys and copper substrate: a short review
    (IOP Publishing Ltd., 2020)
    Chi Ying Tan
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    ;
    This paper is aimed to review and study the interfacial reaction between SnAgCu (SAC) lead-free solder alloys and common copper substrates. Among the lead-free solders, a ternary solder alloys, SnAgCu (SAC) based solder, is leading the lead-free solders as it has excellent thermal and electrical properties. The interfacial between solder alloy and substrate comprise an important characteristic in the reliability performance of a solder alloy. As the current industry has driven to miniaturization, high integration and multifunctionality, the reliability and durability of solder joints are gained attention for its long-term performance of electronic products. Therefore, in this short review, the interfacial reaction between SAC solder alloys and copper substrate will be focused. Besides, the effects of the addition of microalloying elements into SAC solder alloys will be discussed.
      35  1
  • Publication
    Performance of Sn-3.0Ag-0.5Cu composite solder with Kaolin geopolymer ceramic reinforcement on microstructure and mechanical properties under isothermal ageing
    ( 2021)
    Nur Syahirah Mohamad Zaimi
    ;
    ;
    Andrei Victor Sandu
    ;
    ; ; ;
    Petrica Vizureanu
    ;
    ;
    Mohd Izrul Izwan Ramli
    This paper elucidates the effect of isothermal ageing at temperature of 85 °C, 125 °C and 150 °C for 100, 500 and 1000 h on Sn-3.0Ag-0.5Cu (SAC305) lead-free solder with the addition of 1 wt% kaolin geopolymer ceramic (KGC) reinforcement particles. SAC305-KGC composite solders were fabricated through powder metallurgy using a hybrid microwave sintering method and reflowed on copper substrate printed circuit board with an organic solderability preservative surface finish. The results revealed that, the addition of KGC was beneficial in improving the total thickness of interfacial intermetallic compound (IMC) layer. At higher isothermal ageing of 150 °C and 1000 h, the IMC layer in SAC305-KGC composite solder was towards a planar-type morphology. Moreover, the growth of total interfacial IMC layer and Cu3Sn layer during isothermal ageing was found to be controlled by bulk diffusion and grain-boundary process, respectively. The activation energy possessed by SAC305-KGC composite solder for total interfacial IMC layer and Cu3Sn IMC was 74 kJ/mol and 104 kJ/mol, respectively. Based on a lap shear test, the shear strength of SAC305-KGC composite solder exhibited higher shear strength than non-reinforced SAC305 solder. Meanwhile, the solder joints failure mode after shear testing was a combination of brittle and ductile modes at higher ageing temperature and time for SAC305-KGC composite solder.
      2  15
  • Publication
    The microstructure evolution and activation energy study of Cu₆Sn₅ and Cu₃Sn intermetallic compound layer of Sn-10Cu/Cu solder joint
    ( 2024-03)
    Muhammad Amirul Aiman A. Ramlee
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    ;
    Nur Syahirah Mohamad Zaimi
    ;
    The electronic packaging industry is gradually moving away from lead solder to lead-free solder, which is more environmentally friendly. However, there is still work to be done to ensure that lead-free solder meets the demands and requirements of the latest technology. The present study demonstrates the analysis of the microstructure formation of Cu₆Sn₅ and Cu₃Sn intermetallic compound layers in Sn-10Cu/Cu solder joints. Therefore, the key objective of this research is to determine the growth rate and activation energy of the Cu₆Sn₅ and Cu₃Sn intermetallic compound layer of the Sn-10Cu/Cu solder joint. The investigation on the bulk solder microstructure which consists of Cu₆Sn₅ and Cu₃Sn intermetallic compound layer was carried out using Optical Microscope (OM), Scanning Electron Microscope (SEM) with EDX and ImageJ software. The IMC layer undergoes rapid growth with increasing aging temperature and duration and the two main IMC layers (Cu₆Sn₅ and Cu₃Sn) grew thicker. The growth kinetic solder joints for Sn-10Cu and Sn-0.7Cu are 22.44 kJ/mol and 31.20 kJ/mol, respectively. Hence, the findings from this study may offer useful information for the development of high-reliability solder joints in future applications.
      11  20