Norainiza Saud

Microstructural Observation and Phase Analysis of Sn-Cu-Ni (SN100C) Lead Free Solder with Addition of Micron-Size Silicon Nitride (Si3N4) Reinforcement

The effect of micron-size silicon nitride (Si3N4) particles additions, up to 1.0 wt. % on Sn-Cu-Ni (SN100C) solder alloy was investigated. Sn-Cu-Ni composite solder were prepared via powder metallurgy (PM) technique. Different percentages of Si3N4 (0, 0.25, 0.5, 0.75 and 1.0 wt. %) were added into the alloy. Result revealed that reinforcement was well distributed between the grain boundaries which could positively affect the properties of the composite solder.

Isothermal Aging Affect to the Growth of Sn-Cu-Ni-1 wt.% TiO2 Composite Solder Paste

This work investigated the effects of 1.0 wt. % TiO2 particles addition into Sn-Cu-Ni solder paste to the growth of the interfacial intermetallic compound (IMC) on Cu substrate after isothermal aging. Sn-Cu-Ni solder paste with TiO2 particles were mechanically mixed to fabricate the composite solder paste. The composite solder paste then reflowed in the reflow oven to form solder joint. The reflowed samples were then isothermally aged 75, 125 and 150 ° C for 24 and 240 h. It was found that the morphology of IMCs changed from scallop-shape to a more uniform planar shape in both Sn-Cu-Ni/Cu joints and Sn-Cu-Ni-TiO2 /Cu joint. Cu6Sn5 and Cu3Sn IMC were identified and grew after prolong aging time and temperature. The IMCs thickness and scallop diameter of composite solder paste were reduced and the growth of IMCs thickness after isothermal aging become slower as compared to unreinforced Sn-Cu-Ni solder paste. It is suggested that TiO2 particles have influenced the evolution and retarded the growth of interfacial IMCs.

Effect of TiO2 Reinforcement on Microstructure and Microhardness of Low-Silver SAC107 Lead-Free Solder Composite Solder

This research has investigated the physical performances of low-silver Sn-Ag-Cu (SAC) lead-free composite solder reinforced with titanium dioxide (TiO2). The SAC/TiO2 composite solder were fabricated via powder metallurgy (PM) technique. The five different composition chosen were 0, 0.25, 0.5, 0.75, and 1.0. The results showed that distribution of TiO2 along the grain boundaries has increased the hardness of the SAC/TiO2 composite solders compared to monolithic SAC solder alloy.

Microstructural and phase analysis of Sn-Cu-Ni-XSiC composite solder

The effect of ceramic addition on the Sn-Cu-Ni solder alloy microstructure has been investigated. Sn-Cu-Ni/SiC composite solder samples were fabricated via powder metallurgy (PM) techniques. In this study, five different SiC composition were chosen (0 wt. %, .25 wt. %, 0.5 wt. %, 0.75 wt. %, and 1.0 wt. %). The results revealed that a small amount of SiC addition has well distributed along the grain boundaries which also refines the β-Sn phase.The effect of ceramic addition on the Sn-Cu-Ni solder alloy microstructure has been investigated. Sn-Cu-Ni/SiC composite solder samples were fabricated via powder metallurgy (PM) techniques. In this study, five different SiC composition were chosen (0 wt. %, .25 wt. %, 0.5 wt. %, 0.75 wt. %, and 1.0 wt. %). The results revealed that a small amount of SiC addition has well distributed along the grain boundaries which also refines the β-Sn phase.

Effect of TiO2 on the Formation of Primary and Interfacial Cu6Sn5 in Sn-0.7wt%Cu and Sn-0.7wt%Cu-0.05wt%Ni Solder Paste during Soldering

This paper investigates the effect of 1 wt% TiO2 on the formation of primary and interfacial Cu6Sn5 in Sn-0.7wt%Cu and Sn-0.7wt%Cu-0.05wt%Ni solder pastes soldered on a Cu substrate using a real-time synchrotron imaging technique. It was found that TiO2 had altered the nucleation time of the primary Cu6Sn5 intermetallics and increased the number of particles observed. In addition, a more planar Cu6Sn5 interfacial layer had formed in joints made with TiO2 reinforced solders. This indicated that TiO2 promotes nucleation of primary Cu6Sn5 intermetallics in the early stages of soldering while being a barrier for further growth of interfacial Cu6Sn5 intermetallics. The synchrotron imaging technique provides direct evidence of the sequence of events in the soldering reaction and how these are influenced by TiO2 reinforcement.

Effect of Si3N4 Addition on the Properties of Sn-1.0Ag-0.7Cu Solder Alloy

This research has investigated the properties of low-silver Sn-1.0Ag-0.7Cu (SAC107) alloy. Different weight percentages (0, 0.25, 0.5, 0.75 and 1 wt. %) of silicon nitride (Si3N4) were used as reinforcement particles. The SAC107 - Si3N4 composite solder was fabricated via powder metallurgy (PM) technique. The results showed that homogeneous distribution of Si3N4 particles along the grain boundaries has increased the hardness of the SAC107 - Si3N4 composite solders compared to monolithic SAC107 solder alloy. The melting temperature is maintained at the SAC107 level, indicating that the novel composite solder is suitable for existing soldering process.

The Influence of Activated Carbon (AC) on Melting Temperature, Wettability and Intermetallic Compound Formation of Sn-Cu-Ni (SN100C) Solder Paste

This paper reports on the effect of activated carbon (AC) addition on the properties of Sn-Cu-Ni (SN100C) solder paste. The composite solder was prepared by mixing reinforcement particles (0, 0.25, 0.5, 0.75 and 1.0 wt. %) into SN100C solder paste. The melting temperature of composite solder was determined by using differential scanning calorimetry (DSC). Wettability of fabricated solder was studied through contact angles between solder and copper substrate interface. The intermetallic compound formation was studied after reflow soldering process.With increased carbon particles addition, the composite solder was found to have a slightly lower melting temperature compared to monolithic solder while the wettability of composite solder effectively had improved. The activated carbon particles in solder paste composite have significant effects on the formation of intermetallic compounds (IMCs) at the solder/Cu substrate interfaces by suppressing the IMCs thickness.

Effect of SiC Particles Addition on the Wettability and Intermetallic Compound Layer Formation of Sn-Cu-Ni (SN100C) Solder Paste

The effects of SiC on wettability and intermetallic compound (IMC) formation of Sn-Cu-Ni solder paste composite were systematically investigated. Lead-free solder paste composite was produced by mixing silicon carbide (SiC) particle with Sn-Cu-Ni (SN100C) solder paste. The wettability of composite solder was studied by observing the contact angle between solder and copper substrate. The IMC phase formation on copper substrate interface was identified using X-ray diffraction (XRD). The phase as detected in the composite solder is Cu6Sn5.The wettability of composite solder was observed through contact angle between solder and copper substrate and Sn-Cu-Ni + 1.0 wt.% SiC shows improvements in wetting angle and suppresses the IMCs formation.

Effect of Aluminium Addition on Microstructure and Microhardness of Sn-0.7Cu-xAl Lead-Free Solder Alloy

The effect of Al particles addition on the microstructure and microhardness of Sn-0.7Cu-xAl lead-free solder was systematically investigated. The Sn-0.7Cu-xAl solder alloy was successfully fabricated via powder metallurgy (PM) method which consists of mixing, compaction and sintering. Results show that the crystallization of Sn occurs in two different modifications; α-Sn and β-Sn, where the formation of β-Sn able to reinforce the solder matrix. The Al particles also distributed homogeneously along the grain boundaries. The microhardness was improved by 19% as the weight percentage of the Al particles increased up to 1.0 wt.%.

Mechanical Properties and Solderability of Robust Sn-0.7Cu Lead-Free Composite Solder

A composite solder with Sn-0.7Cu based solder was successfully fabricated via powder metallurgy routes which consist of mixing, compacting and sintering. Varying amount of activated carbon (AC) was used as reinforcement to obtain a novel lead-free composite solder. Following fabrication, the sintered composite solder was analyzed in terms of their microstructure, microhardness and solderability properties. The distribution of the various percentages of AC particles along the grain boundaries was observed. The addition of AC particles into the Sn-0.7Cu solder matrix has increased the hardness values up to 22.9%, while reducing the contact angle of composite solder up to 12.9% for a good wettability performance. As overall, addition of AC into Sn-0.7Cu based solder has indicated an enhancement of reliability performance of Sn-0.7Cu/AC composite solder for electronic application.