Investigation of the Wetting Properties of Ternary Lead-Free Solder Alloys on Copper Substrate

The effects of antimony and indium addition on wettability and interfacial reaction of Sn-3.0Ag-0.5Cu lead free solder on copper substrate were investigated. The experimental results showed the melting point of solder alloy containing 0.5 wt.% In and 0.5 wt.% Sb were slightly increased about 3.66°C. The pasty range of solder alloys were increased about 6°C while the undercooling of solder alloys were decreased. The microstructures of solder alloy were contained of In and Sb consists of Ag3Sn, Cu6(Sn,In)5, SnIn, Ag3(Sn,In) and SnSb intermetallic compounds (IMCs) dispersed on Sn-rich phase. The wettability of solder alloys were improved by increasing soldering times. In addition, the thickness of intermetallic compounds (Cu6Sn5) were obviously increased with increasing soldering times.

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INTERMETALLIC COMPOUNDS FORMATION OF SOLDER ALLOYS ON Ni/Au SURFACE FINISH COPPER

Acta Metallurgica Slovaca ◽

10.36547/ams.26.4.707 ◽

2020 ◽

Vol 26 (4) ◽

pp. 184-187

Author(s):

Ngoc Binh Duong

Keyword(s):

Intermetallic Compounds ◽

Melting Temperature ◽

Surface Finish ◽

Copper Substrate ◽

Lead Free ◽

Lead Free Solder ◽

Solder Alloys ◽

Soldering Temperature ◽

Substrate Interface ◽

Free Solder

Intermetallic compounds (IMCs) formation between lead-free solder alloys (Sn-9Zn and Sn-8Zn-3Bi) and Ni/Au surface finish copper substrate were studied. Reaction between the solder and the substrate was carried out at regular soldering temperature, approx. 50 °C above the melting temperature of the solder alloys. Results indicated that Au-Zn was the IMC formed at the interface and the Au layer which is electro-plated on the substrate has completely dissolved into the solder alloys. The amount of Au available at the interface is an important factor that influent the morphology of the IMC with thicker Au layer on the substrate resulted in thicker layer of IMC at the interface. Although Bi does not taken part in the composition of IMC, it influent the formation of IMC, the IMC formed in the Sn9Zn/substrate interface was Au5Zn3, meanwhile it was g2-AuZn3 in the Sn-8Zn-3Bi/substrate interface.

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Effect of rare earth Ce on the microstructure, physical properties and thermal stability of a new lead-free solder

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb1101011c ◽

2011 ◽

Vol 47 (1) ◽

pp. 11-21 ◽

Cited By ~ 23

Author(s):

W. Chen ◽

J. Kong ◽

W.J. Chen

Keyword(s):

Rare Earth ◽

Melting Temperature ◽

Lead Free ◽

Lead Free Solder ◽

Solder Alloys ◽

Wetting Properties ◽

Wetting Property ◽

Cast Alloys ◽

Free Solder ◽

Induced Aggregation

In this paper, in order to develop a low silver content lead-free solder with good overall properties, a newly designed solder alloys of Sn-0.3Ag-0.7Cu-20Bi-xCe type, with addition of varying amounts of rare earth Ce (0.05 mass%, 0.1 mass% and 0.2 mass%) were studied. The melting temperature of Sn-0.3Ag- 0.7Cu can be decreased substantially through addition of 20 mass% Bi; while the segregation of Bi element in the microstructure of the as-cast alloys can be relieved by micro-alloying with trace amount of rare earth Ce. Besides, aging treatments (160?C held for 6 h) of these solder alloys imply that appropriate amount of Ce addition can not only depress the diffusion induced aggregation of Bi in the microstructure but promote the homogenization during annealing. Compared with Bi-free Sn-0.3Ag-0.7Cu solder, Sn-0.3Ag-0.7Cu- 20Bi exhibits better wettability. More excitingly, the wetting property of Sn-0.3Ag-0.7Cu-20Bi can be further improved by doping little amounts of Ce, especially 0.5 mass%, in which case the spreading area of the solder can be increased to the largest extent. On the whole, the present study reveals that Sn-0.3Ag-0.7Cu- 20Bi-xCe (x=0.05-0.1) is a promising lead-free solder candidate considering the microstructure, melting temperature and wetting properties.

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Interfacial Reaction and Solderability of Zn20SnxCu Solder

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.337.402 ◽

2011 ◽

Vol 337 ◽

pp. 402-405

Author(s):

Kuai Le Zhao ◽

Yan Fu Yan ◽

Yang Yang Sheng ◽

Ning Du ◽

Zhan Lei Liu

Keyword(s):

High Temperature ◽

Melting Point ◽

Intermetallic Compound ◽

Interfacial Reaction ◽

Low Cost ◽

Copper Substrate ◽

Lead Free ◽

Lead Free Solder ◽

Solder Alloys ◽

Free Solder

Zn20Sn solder with the melting point of 383.9°C and a low cost is considered as an ideal high-temperature lead-free solder. In the paper a new solder alloys were made by adding trace Cu into Zn20Sn alloy through alloying principle. Interfacial reaction and solderability of Zn20SnxCu (x=0 wt.%, 2 wt.%, 4 wt.% and 6 wt.%) solder on the copper substrate were investigated. Results showed that β’-CuZn, γ-Cu5Zn8 and ε-CuZn5 IMC layers were formed at the interface of Zn20SnxCu/Cu. The spreading areas of the Zn20SnxCu solders were reduced linearly with the increasing of the content of copper. The spreading aera of Zn20Sn solder was 52.88 mm2 while that of Zn20Sn6Cu was 50.82mm2 which was approximately 3.9% smaller than that of matrix solder. It is mainly related to the formation of ε-CuZn5 phase and the metal intermetallic compound between the solder and the substrate.

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Wetting characteristic of Sn-(3-x)Ag-0.5Cu-xBi quaternary solder alloy systems

Soldering & Surface Mount Technology ◽

10.1108/ssmt-08-2018-0028 ◽

2019 ◽

Vol 32 (1) ◽

pp. 19-23 ◽

Cited By ~ 3

Author(s):

Ahmet Mustafa Erer ◽

Serkan Oguz

Keyword(s):

Solder Alloy ◽

Sessile Drop ◽

Lead Free ◽

Lead Free Solder ◽

Solder Alloys ◽

Content Type ◽

Cu Substrate ◽

Wetting Properties ◽

Free Solder ◽

Drop Technique

Purpose This paper aims to invastigate of the wetting and interfacial properties of Sn-(3-x)Ag-0.5Cu-(x)Bi (x = 0.5, 1 and 2 in Wt.%) Pb-free solder alloys at various temperatures ( 250, 280 and 310°C) on Cu substrate in Ar atmosphere. Design/methodology/approach In this study, new Sn-(3-x)Ag-0.5Cu-xBi systems, low Ag content quaternary lead-free solder alloys, were produced by adding 0.5, 1 and 2% Bi to the near-eutectic SAC305 alloy. The wetting angles of three new alloys, Sn-2.5Ag-0.5Cu-0.5 Bi(SAC-0.5 Bi), Sn-2Ag-0.5Cu-1Bi(SAC-1Bi) and Sn-1Ag-0.5Cu-2Bi(SAC-2Bi) were measured by sessile drop technique on the Cu substrate in argon atmosphere. Findings In accordance with the interfacial analyses, intermetallic compounds of Cu3Sn, Cu6Sn5, and Ag3Sn were detected at the SAC-Bi/Cu interface. The results of wetting tests show that the addition of 1 Wt.% Bi improves the wetting properties of the Sn-3Ag-0.5Cu solder. The lowest wetting angle (θ) was obtained as 35,34° for Sn-2Ag-0.5Cu-1Bi alloy at a temperature of 310 °C. Originality/value This work was carried out with our handmade experiment set and the production of the quaternary lead-free solder alloy used in wetting tests belongs to us. Experiments were conducted using the sessile drop method in accordance with wetting tests.

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Wetting and Intermetallic Study between Sn-3.5Ag-1.0Cu-xZn Lead-Free Solders and Copper Substrate (x = 0, 0.1, 0.4, 0.7)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.501.150 ◽

2012 ◽

Vol 501 ◽

pp. 150-154 ◽

Cited By ~ 9

Author(s):

Ramani Mayappan

Keyword(s):

Copper Substrate ◽

Electronics Industry ◽

Lead Free ◽

Lead Free Solder ◽

Solder Alloys ◽

Spreading Area ◽

Cu Substrate ◽

Soldering Time ◽

Free Solder ◽

Lead Free Solders

The development of lead-free solders has been an essential task in the electronics industry because of the restriction of lead use by legislation. Among the candidates, Sn-Ag-Cu group of solder alloys have great advantages to replace the conventional Sn-Pb solder. In this study, the wetting and intermetallic study between Sn-3.5Ag-1.0Cu-xZn lead-free solder reacting on copper substrate were investigated under different soldering conditions. The addition of 0.7wt% of Zn improved the wettability on Cu substrate since it has the highest spreading area at 310°C. The Cu6Sn5 and Cu3Sn phases are the main interface intermetallic formed and these intermetallics increased in thickness with time and temperature. At 270°C, the addition of 0.7wt% Zn retarded the growth of Cu3Sn intermetallic until 10 min of the soldering time. Generally the addition of Zn was beneficial in retarding the total intermetallic thickness.

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