Sains Malaysiana 38(3): 395-400(2009)

Temperature and Flux Effect on Contact Angles and Intermetallic

between Sn-8Zn-3Bi Lead-free Solder and Cu Substrate

(Kesan Suhu dan Fluks terhadap Sudut Sentuhan dan Antaramuka di antara

Pateri Bebas Plumbum Sn-8Zn-3Bi dan Substrat Cu)

Ramani Mayappam*

University Technology Mara, Perlis Branch

02600-Arau, Perlis, Malaysia

Zainal Arifin Ahmad

School of Materials and Minerals Resources Engineering

Engineering Campus, Universiti Sains Malaysia

14300 Nibong Tebal, Pulau Pinang, Malaysia

Received: 28 May 2008 / Accepted: 19 August 2008

Abstract

The influences of temperatures and fluxes on contact angles, intermetallic phase and thickness of Sn-40Pb and Sn-8Zn-3Bi solders on copper substrate were investigated. As expected, the contact angle decreases and the intermetallic thickness increases as the temperature increases. The Sn-40Pb solder exhibits a lower contact angles compared to Sn-8Zn-3Bi solder for all the fluxes tested. The Sn-40Pb/Cu system exhibits a single Cu₆Sn₅ intermetallic. The Sn-8Zn-3Bi/Cu interface exhibits ε(Cu-Zn) and γ-Cu₅Zn₈ phases and soldering at 280^oC exhibits a single g-Cu₅Zn₈ phase. Sn-40Pb/Cu gives higher intermetallic thickness compare to Sn-8Zn-3Bi/Cu system when soldering was done at 220^oC. On the other hand, the IMC thickness formed by Sn-8Zn-3Bi/Cu system is higher than Sn-40Pb/Cu system for all other temperatures. Although, the fluxes have no significant influence on the thickness of IMC formed, ZnCl₂ generally gives lower IMC thickness.

Keywords: Contact angle; flux; intermetallic; Pb-free solder; Sn-Zn-Bi

ABSTRAK

Kesan suhu dan fluks terhadap sudut sentuhan, fasa dan ketebalan antaramuka pateri Sn-40Pb dan Sn-8Zn-3Bi dengan substrat Cu telah dikaji. Seperti diduga, sudut sentuhan berkurangan dan ketebalan antaramuka bertambah bila suhu bertambah.  Pateri Sn-40Pb mempamerkan sudut sentuhan yang kecil berbanding dengan pateri Sn-8Zn-3Bi untuk ke semua fluks yang dikaji. Sistem Sn-40Pb/Cu mempamerkan antaramuka Cu₆Sn₅ yang tunggal. Sistem Sn-8Zn-3Bi/Cu mempamerkan fasa-fasa ε(Cu-Zn) and γ-Cu₅Zn₈ dan memateri pada suhu 280^oC menghasilkan menghasilkan fasa γ-Cu₅Zn₈ yang tunggal. Ketebalan antaramuka pada suhu 220^oC untuk sistem Sn-40Pb/Cu adalah lebih besar daripada sistem Sn-8Zn-3Bi/Cu untuk suhu-suhu yang lain. Walaupun fluks tidak  mempengaruhi ketebalan antaramuka, tetapi ZnCl₂ memberi ketebalan yang kurang berbanding dengan fluks yang lain.

Kata kunci: Antaramuka; fluks; Pateri tanpa Pb; Sn-Zn-Bi; sudut sentuhan

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*Corresponding author; email: rasiadi@yahoo.com.my