Indium Blog

Die-Attach Soldering Using Indium Alloys

There are at least three significant reasons to use indium solder alloys in your die-attach operation: Physical performance, Supplier reliability, Material dependability:


Indium-containing solder paste is very well proven in low temperature usage, however it is also used in some specific high-temperature die-attach applications. A major Chinese die-attach customer recently confirmed that our high-melting solder paste (using Indalloy 164, 95.5Pb/5In/2.5Ag) is pretty much irreplaceable in their niche application for several reasons including:

  1. reliability of the final solder joint
  2. controlled wetting of the die and leadframe surfaces, to control die tilt and skewing



Indium Corporation is a preferred, vertically-integrated supplier since our founding in 1934 because of our Quality Systems. This differentiates Indium Corporation as a company because not just our customers, but their customers need assurance that the entire supply chain is robust and reliable.

And, there is a third issue that I am pleased to mention:


In spite of what some misinformed alarmists have recently been claiming, indium metal is very abundant – more so than silver. And, it is so available that prices have recently been falling. A good sign!

Materials prices fluctuate due to several factors, including supply, demand, processing capacities, and many more. Indium supply and availability has remained dependable since its commercialization nearly 100 years ago. Indium Corporation’s vertical integration assures you that we are in intimate contact with the entire sourcing process, from mining, to refining, to final materials fabrication.

So, feel comfortable specifying and designing indium-containing solder alloys into your die-attach BOM. It is physically compatible, comes from a highly-reliable vendor, and has a proven dependable supply.

If you have any questions, please contact me.