Introduction

Lead-Free Initiative™

The history of soldering goes back some 5,000 years, but fundamental soldering has always used Sn-Pb series solder that consists of tin and lead. However, lead pollution ground water has been recognized as an environmental problem and complete elimination of the use of lead is called for.

Realizing that protection of our environment is our task in the 21st century, SMIC has earnestly extended our research in this area and developed Lead-Free "ECO SOLDER."

Please contact us for any problem that relates to Lead-Free soldering. We are thoroughly prepared to introduce Lead-Free soldering system as we have a comprehensive technology base and have constructed support systems in various phases with ECO Soldering Solution™.

JIS Z 3282 / ISO9453: Chemical composition of lead-free solders

Class	Symbol		SMIC Item
	1	2
Sn 96.5 Ag 3 Cu 0.5	Sn 96.5 Ag 3 Cu 0.5	A30C5	M705

Chemical Composition Mass％
Sn	Pb	Sb	Bi	Cu	Au	In	Ag	Al	As	Cd	Fe	Ni	Zn
Remain	0.10 max	0.10 max	0.10 max	0.3 to 0.7	0.05 max	0.10 max	2.8 to 3.2	0.001 max	0.03 max	0.002 max	0.02 max	0.01 max	0.001 max

* SMIC's lead-free alloys are produced impurity less than 0.05%.

ECO SOLDER

Lead-Free ECO SOLDER developed by SMIC offers high soldering reliability compared with the Sn-Pb series solder of the past and is available in a wide product lineup according to the required soldering temperature.

E series（antioxident type）and automatic feeding type for solder bath are also available.

Product availability may be limited for certain alloy compositions. Please select the appropriate product from the ECO SOLDER Products Guide below.

ECO SOLDER Products Guide

Item	Alloy composition (wt%)	Temp. (°C) Solidus line / Peak[1] / Liquidus line			Form					Remarks
					Bar	Wire	Flux Cored	Ball	Paste
M-series: Solidus line temp. 200 to 250 °C
M705	Sn-3.0 Ag-0.5 Cu	217	219	220						*1
M31	Sn-3.5Ag-0.75Cu	218	219	219						*1
M35	Sn-0.7Cu-0.3Ag	217	219	227						*2
M771	Sn-1.0 Ag-0.7 Cu	217	219	224						*2
M10	Sn-5.0Sb	240	243	243
M14	Sn-10Sb	245	248	266
M20	Sn-0.75Cu	227	229	229
M24E	Sn-0.70Cu-0.03Ni-P	228	230	230						*3
M30	Sn-3.5Ag	221	223	223
M34	Sn-1.0Ag-0.5Cu	217	219	227
M37	Sn-4.0Ag-0.9Cu	217	219	230						*4
M42	Sn-2.0Ag-0.75Cu-3.0Bi	207	214	218						*5
M52	Sn-1.0 Ag-0.1 Cu-0.05 In-0.02Ni	218	219	228
M707	Sn-2.0Ag-0.5Cu	217	218	223
M714	Sn-3.8 Ag-0.7 Cu	217	219	225
M715	Sn-3.9Ag-0.6Cu	217	219	226
M716	Sn-3.5Ag-0.5Bi-8.0ln	197	208	214						*6
M731	Sn-3.9 Ag-0.6 Cu-3.0 Sb	221	224	226
DY Alloy	Sn-1.2Ag-4.0Cu	217	225	353
M709	Sn-0.5 Ag-6.0 Cu	217	226	378
M33	Sn-2.0Ag-6.0Cu	213	219	380
L-series: Solidus line temp. under 200 °C
L11	Sn-8.0Zn-3.0Bi	190	197	197
L20	Sn-58Bi	139	141	141
L23	Sn-57Bi-1.0Ag	138	140	204						*7

[1] Peak temp. : Max. endothermic reaction point on DSC curve.

*1: JP PAT No. 3027441, US PAT No. 5527628
*2: Low Ag content alloy on JEITA'S recommendations.
*3: JP PAT No. 3622788, Sn-Cu Alloy for anti-shrinkage cavity
*4: Alloy for anti-shrinkage cavity
*5: US PAT No. 4879096, CN PAT No. 1299471
*6: JP PAT No. 3040929
*7: US PAT No. 5320272