Microstructural analysis of Sn-3.0Ag-0.5Cu-TiO₂ composite solder alloy after selective electrochemical etching

Abstract

This work aims to provide deep morphological observation on the incorporated TiO 2 nanoparticles within the SAC305 by selective electrochemical etching. Cyclic voltammetry and chronoamperometry were used to investigate the selective etching performances. The removal of β-Sn matrix was conducted at a fixed potential of −350 mV. Average performances of 2.19 and 2.30 mA were attained from the chronoamperometry. The efficiency of β-Sn removal was approved according to the reduction of the intensities on the phase analysis. Successful observation of the TiO 2 near the Cu 6 Sn 5 layer was attained for an optimum duration of 120 s. Clusters of TiO 2 nanoparticles were entrapped by Cu 6 Sn 5 and Ag 3 Sn intermetallic compound (IMC) layer network and at the solder/substrate interface. The presence of TiO 2 nanoparticles at the solder interface suppresses the growth of the Cu 6 Sn 5 IMC layer. The absence of a β-Sn matrix also allowed in-depth morphological observations to be made of the shape and size of the Cu 6 Sn 5 and Ag 3 Sn. It was found that TiO 2 content facilitates the β-Sn removal, which allows better observation of the IMC phases as well as the TiO 2 reinforcement particles.

Effect of Kaolin Geopolymer Ceramics Addition on the Microstructure and Shear Strength of Sn-3.0Ag-0.5Cu Solder Joints during Multiple Reflow

“…As the quality and reliability of solder joints are dependent on the formation of IMC layers, many researchers took the initiative to enhance the performance of existing Pb-free solder alloys. One of the feasible and viable approaches was using ceramics materials to form composite solders [17][18][19][20][21]. To date, there are various ceramic materials that had been successfully added into the solder matrix, such as silicon carbide (SiC) [12], titanium oxide (TiO 2 ) [17,18,22], titanium carbide (TiC) [22], samarium oxide (Sm 2 O 3 ) [23], alumina (Al 2 O 3 ) [24], and cerium oxide (CeO 2 ) [25,26].…”

The influence of SACX0307-ZnO nanocomposite solder alloys on the optical and thermal properties of power LEDs

“…Also, Cu 6 Sn 5 and Ag 3 Sn spacing were lower. The Ag 3 Sn IMCs are incorporated at the grain boundaries of the Sn matrix, as was described earlier by Yahaya et al (2020), so the Sn grain boundaries can be located according to the Ag 3 Sn network in the solder bulk. The grain boundaries are marked by red dashed lines in Figure 9.…”

The Influence of Soldering Profile on the Thermal Parameters of Insulated Gate Bipolar Transistors (IGBTs)

“…The increase in R th values was probably caused by the microstructure changes in the solder joint. Typically, the SAC solder joints are composed of the β-Sn matrix and intermetallic compounds (IMCs), such as Cu 6 Sn 5 , Cu 3 Sn, and Ag 3 Sn [23]. IMCs presented both in the solder bulk as isolated dissolved islands and as an IMC layer (typically Cu 6 Sn 5 ) between Cu pad and solder alloy.…”