The history of soldering goes back some 5,000 years ago, but fundamental soldering has always been the Sn-Pb series solder that consists of tin and lead. However, lead pollution in groundwater 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 solder "ECO SOLDER." Please contact for any problem that relates to Lead-Free soldering. We are thoroughly prepared to introduce a Lead-Free soldering system as we have a comprehensive technology base and have constructed support systems in various phases.

Comparison of typical Lead-Free alloy M705 and Sn63 characteristics

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. 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
M10	Sn-5.0Sb	240	243	243
M20	Sn-0.75Cu	227	229	229
M24E	Sn-0.70Cu-0.03Ni-P	228	230	230						*7
M30	Sn-3.5Ag	221	223	223
M31	Sn-3.5Ag-0.75Cu	218	219	219						*1
M34	Sn-1.0Ag-0.5Cu	217	219	227
M35	Sn-0.7Cu-0.3Ag	217	219	227
M37	Sn-4.0Ag-0.9Cu	217	219	230						*6
SA2515	Sn-2.5Ag-1.0Bi-0.5Cu	214	221	221						*2
M42	Sn-2.0Ag-0.75Cu-3.0Bi	207	214	218						*2
M51	Sn-3.0Ag-0.7Cu-1.0In	214	217	217
M704	Sn-3.35Ag-0.7Cu-0.3Sb	218	219	220						*3
M705	Sn-3.0Ag-0.5Cu	217	219	220						*1
M706	Sn-3.0Ag-0.7Cu-1Bi-2.5In	204	213	215
M707	Sn-2.0Ag-0.5Cu	217	218	223
M715	Sn-3.9Ag-0.6Cu	217	219	226
M716	Sn-3.5Ag-0.5Bi-8.0ln	197	208	214						*4
DY Alloy	Sn-1.2Ag-4.0Cu	217	225	353
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
L21	Sn-2.0Ag-0.5Cu-7.5Bi	189	208	213
L23	Sn-57Bi-1.0Ag	138	140	204						*5