Interfacial Reactions in the Cu/Ga/Co and Cu/Ga/Ni Samples
To fundamentally understand the solid–liquid interdiffusion joining processes between a Cu electrode and Co and Ni barrier layers using a Ga solder, the interfacial reactions in the Cu/Ga, Co/Ga, Ni/Ga, Cu/Ga/Co and Cu/Ga/Ni samples have been systematically examined. The reaction phases at the Cu/Ga...
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Published in | Journal of electronic materials Vol. 48; no. 6; pp. 3643 - 3654 |
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Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
New York
Springer US
01.06.2019
Springer Nature B.V |
Subjects | |
Online Access | Get full text |
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Summary: | To fundamentally understand the solid–liquid interdiffusion joining processes between a Cu electrode and Co and Ni barrier layers using a Ga solder, the interfacial reactions in the Cu/Ga, Co/Ga, Ni/Ga, Cu/Ga/Co and Cu/Ga/Ni samples have been systematically examined. The reaction phases at the Cu/Ga interface in the Cu/Ga, Cu/Ga/Co and Cu/Ga/Ni samples reacted at 200°C, 350°C and 500°C are all the same, and are γ
3
-Cu
9
Ga
4
and CuGa
2
, γ
2
-Cu
9
Ga
4
and γ
1
-Cu
9
Ga
4
respectively. No Co/Ga interfacial reaction phase was found in either the Co/Ga or Cu/Ga/Co samples reacted at 200°C, and the reaction phase is CoGa
3
when reacted at 350°C and 500°C. The reaction phase in the Ni/Ga couples reacted at 200°C and 350°C is the Ni
3
Ga
7
phase while it is Ni
2
Ga
3
at 500°C. In the Cu/Ga/Ni samples, no Ni/Ga interfacial reaction phase is observed at 200°C, and the Ni
3
Ga
7
and Ni
2
Ga
3
phases formed at 350°C and 500°C have 8.5 at.%Cu and 14.0 at.%Cu solubilities. The growth rates of the reaction phases have been determined, and the Ga consumption rates in the Cu/Ga/Co and Cu/Ga/Ni samples at 200°C, 350°C and 500°C were calculated. It is observed that the consumption rates increase with the square root of the reaction time, and the consumption rate constants are 39.2
μ
m/h
0.5
and 77.3
μ
m/h
0.5
, respectively. |
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ISSN: | 0361-5235 1543-186X |
DOI: | 10.1007/s11664-019-07121-w |