摘 要

本文通過采用Sn-8.0Zn-xBi合金在Cu基板上回流焊的方法，研究了Bi對Sn-Zn系合金在Cu基板上焊接界面的影響。利用掃描電子顯微鏡和能譜儀觀察和分析Bi對Sn-Zn系合金以及在Cu基板上焊接界面金屬間化合物種類，形貌，厚度及生長情況的影響。結(jié)果表明：Sn-9Zn焊料是由灰色基體β-Sn相和黑色針狀富Zn相所組成的二元共晶組織。Sn-9Zn-1Bi焊料和Sn-8Zn-3Bi焊料由三相組成：灰色的β-Sn相，黑色針狀的富Zn相和白色片狀的Bi固溶體相。
Sn-9Zn焊料合金焊接后焊接界面處形成的金屬間化合物呈半球狀伸入到焊料內(nèi)。從焊料處往Cu板方向，金屬間化合物的成分依次是Cu-Zn化合物相、Cu6Sn5相。Sn-8Zn-1Bi焊料和Sn-8Zn-3Bi焊料焊后，從焊料處往Cu板方向，金屬間化合物的成分依次是Cu6Sn5相、Cu-Zn化合物相。


關(guān)鍵詞：無鉛焊料，Sn-Zn焊料，界面反應(yīng)，金屬間化合物


ABSTRACT

In this paper, the influence of minor Bi addition on the interfacial reaction between Sn-Zn solders and a Cu layer was studied. Scanning electron microscopy was used to observe the microstructure of IMCs formed between solders and the Cu layer. Phase distribution was determined by energy dispersive spectroscopy. The test results show that: the microstructure of the Sn-9Zn solder was composed of a grey β-Sn phase and a needle-like Zn-rich phase. While the Sn-8Zn-1Bi solder and Sn-8Zn-3Bi solder are constituted by three-phase: the grey β-Sn phase, the needle-like Zn-rich phases and a white Bi-rich phase.
After reflow, the intermetallic compounds formed at the interface between Sn-9Zn solder alloy and Cu substrate was hemisphere-like and grew toward solder matrix. The intermetallic compounds formed between Sn-9Zn solder and the Cu substrate was composed of Cu-Zn phase (close to the solder matrix) and Cu6Sn5 phase (close to the Cu layer). Whereas, after the addition of 1%Bi and 3%Bi into the solders, the interfacial reaction intermetallic compounds was composed of Cu6Sn5 phase (close to the solder matrix) and Cu-Zn phase (close to the Cu layer).


Key words：Lead-free solder, Sn-Zn solder, interfacial reaction, Intermetallic compound







目 錄

中文摘要 I
ABSTRACT II
1 緒論 1
1.1引言 1
1.2國內(nèi)外電子封裝無鉛釬料的研究現(xiàn)狀 1
1.3無鉛釬料合金的研究成果 4
1.4課題研究的意義 8
2 實(shí)驗(yàn) 10
2.1 實(shí)驗(yàn)材料及過程 10
2.2 試樣的制備 10
2.3 實(shí)驗(yàn)設(shè)備 11
2.3.1掃描電子顯微鏡 11
2.3.2能譜儀 13
3 實(shí)驗(yàn)數(shù)據(jù)以及結(jié)果分析 15
3.1 焊料合金的顯微組織分析 15
3.2 焊后界面能譜分析 16
3.3實(shí)驗(yàn)結(jié)果分析 19
3.3.1釬焊過程中金屬間化合物的生長過程 19
3.3.2 Cu-Zn 金屬間化合物生長的驅(qū)動(dòng)力 21
3.3.3 釬焊過程中Cu-Zn金屬間化合物的溶解過程 21
4 結(jié)論 24
參考文獻(xiàn) 25