Properties and Applications
Indium is extracted primarily from indium-bearing zinc or tin ores and purified to various grades utilizing state-of-the-art statistical process controlled refining technologies.
No other metal is as versatile as indium metal. In its various forms it is used for:
- Sealing in cryogenic applications – stays malleable and ductile below -150°C
- Soldering or fusing applications – alloys melt at temperatures ranging from 6.5°C to 310°C
- High-end device cooling – reduces operating temperatures by up to 10°C
In addition to its metallic properties, indium also exhibits valuable semiconducting properties. For instance, indium is used:
- As an absorber layer material in solar panels to convert photons from the sun into usable electricity.
- In a variety of compound semiconductor material, such as InAs, InGaAs, and InGaN, to enable electronics and electro-optic applications like integrated circuits, lasers, and LEDs.
Indium is also used in combination with various semiconducting oxides, where it plays its most valuable role as a transparent conductor. ITO (indium-tin oxide) is used on nearly every flat panel display and touchscreen in use today. In fact, IGZO (combining indium, gallium, and zinc oxides) is the future material of choice for forming the pixel switching transistors in next-generation displays.
Indium sputtering targets are commonly used with CuGa sputtering targets to co-deposit copper, indium, and gallium, in combination with sulfur/selenium, to form the active layer on CIS/CIGS thin film cells. Other forms of indium (such as pellets or shot) can be used to form similar active layers when utilizing evaporative methods of deposition.
Versatile. Conductive. Malleable.
Because of its unique properties with virtually limitless applications, indium is literally all around us.
In addition to solder alloys, thermal interfaces, and solar cells, indium is used in many other applications that you may not be aware of. Almost all flat screens use indium-tin oxide – you could be looking through up to 4 layers of indium to read this page. Indium is also used to bond non-metallic surfaces, create quantum dots, and build stretchable electrical circuits.