Top 10 Indium Uses: Key Applications Ranked

Indium uses are dominated by one application: indium tin oxide (ITO) coatings for flat panel displays, which account for an estimated 75–80% of global indium demand. Unlike most critical minerals, indium is not mined as a primary commodity — it is recovered as a by-product of zinc smelting, a supply structure that caps production growth regardless of price signals. The indium price stood at $557.13/kg (domestic China, SMM benchmark, April 2026), down 8.2% month-on-month from $607.12/kg in March — making it the only element in the tracked critical minerals basket to fall in April. For background on the element itself, see what is indium.

How We Ranked the Top 10 Indium Uses

Entries are ranked by global indium consumption volume and commercial scale as of 2025–2026. Where volume data is estimated, this is flagged. The ranking is inherently lopsided: ITO alone accounts for the majority of the market, and the gap between first and second place is significant. Emerging applications are included where they represent credible near-term volume growth, with pre-commercial status clearly noted.

1. ITO Flat Panel Displays — The Defining Indium Use

Indium tin oxide (ITO) — a transparent conductive oxide comprising roughly 90% indium oxide and 10% tin oxide — is the coating applied to LCD screens, touchscreens, smartphones, tablets, and monitors. ITO sputtering targets are applied via physical vapour deposition to glass substrates, creating a conductive layer invisible to the naked eye. This single application accounts for an estimated 75–80% of annual global indium demand, according to the USGS Mineral Resources Program.

Major consumers of ITO include Samsung Display, LG Display, and China’s BOE Technology Group — the world’s largest LCD panel producer by area shipped. Panel manufacturers source ITO sputtering targets from specialist producers including Umicore and Vital Materials. ITO recycling rates from panel manufacturing scrap have improved significantly, with secondary indium now supplying a meaningful share of refined output, particularly in Japan and South Korea. Demand is broadly stable, tracking global screen shipment volumes rather than growing rapidly.

2. Thin-Film Solar Cells (CIGS) — Growth Application

Copper indium gallium selenide (CIGS) photovoltaic cells use indium as a core photoactive material, achieving conversion efficiencies of 20–23% in commercial production — competitive with polysilicon on a cell basis. CIGS is a niche but established technology, best suited to building-integrated photovoltaics (BIPV) where its flexibility and low-light performance justify a premium over silicon panels.

Key producers include Solar Frontier (Japan), Avancis (Germany, owned by China National Building Material Group), and MiaSolé (USA, owned by Hanergy). CIGS has not achieved the manufacturing scale necessary to challenge silicon on cost, but represents the most credible volume growth story for indium demand over the medium term. Each gigawatt of CIGS capacity requires approximately 20–40 tonnes of indium, depending on cell thickness and recycling rates — a meaningful pull if deployment accelerates.

3. Solders, Alloys, and Bonding Materials

Indium-based solders are used in applications where conventional tin-lead or tin-silver solders fail: cryogenic systems, aerospace components, semiconductor die attachment, and high-reliability hermetic sealing. Indium’s low melting point (156.6°C), high ductility at low temperatures, and ability to bond to non-metallic surfaces including glass and ceramics make it non-substitutable in specific assembly processes.

Indium Corporation (Utica, New York) is the dominant global supplier of indium-based soldering materials, bonding alloys, and thermal interface materials. The company serves defence, aerospace, medical device, and semiconductor packaging customers. This application is mature and grows roughly in line with advanced electronics and aerospace output — not a volume driver, but a high-margin, high-reliability segment.

4. Indium Phosphide (InP) Semiconductors

Indium phosphide (InP) compound semiconductors offer electron mobility approximately four times that of silicon, making them the substrate of choice for high-frequency and high-power applications including fibre optic laser diodes, 5G infrastructure components, data centre optical transceivers, and photodetectors. InP wafers support data transmission at speeds and frequencies unachievable with silicon.

The 5G rollout and continued hyperscaler investment in data centre interconnects are driving sustained demand for InP-based devices. Key wafer producers include Sumitomo Electric (Japan), IQE (UK), and Wafer Works (Taiwan). Indium consumption per unit is small relative to ITO, but the per-kilogram value of processed InP devices is orders of magnitude higher — this is where indium’s strategic value is most concentrated.

5. InGaN LEDs and Laser Diodes

Indium gallium nitride (InGaN) is the compound semiconductor behind virtually all blue and white LEDs, as well as the blue laser diodes used in Blu-ray disc systems. The commercial development of InGaN-based blue LEDs by Isamu Akasaki, Hiroshi Amano, and Shuji Nakamura earned the 2014 Nobel Prize in Physics — described by the Nobel Committee as enabling a fundamental new way to create white light.

Indium content in InGaN LEDs is small per unit, but cumulative demand across the global LED market — estimated at tens of billions of units annually — creates a meaningful aggregate consumption figure. The transition from fluorescent and incandescent lighting to LED is now largely complete in mature markets, so demand growth here tracks new construction and replacement cycles rather than technology adoption.

6. Bearings and Engine Coatings

Electroplated indium coatings on engine bearings provide corrosion resistance, improved load-bearing properties, and resistance to fatigue under cyclic stress. This application is used in aerospace piston engines, marine diesel engines, and industrial compressors. Indium-coated bearings offer superior performance to uncoated alternatives in high-load, high-temperature environments where lubricant films break down.

This is a mature, legacy application with limited growth. Indium consumption per bearing is low, and the application has been partly displaced by advanced polymer coatings and ceramic alternatives in some segments. It remains relevant in aerospace overhaul and specialist industrial markets where proven performance data justifies the material cost.

7. Nuclear Reactor Control Rods

Indium-silver-cadmium (In-Ag-Cd) alloy control rods are used in pressurised water reactors (PWRs) — the dominant reactor design globally — to regulate fission rates by absorbing neutrons. The standard alloy composition is approximately 80% silver, 15% indium, and 5% cadmium. Indium is included for its neutron absorption cross-section and its contribution to the alloy’s mechanical properties at elevated temperatures.

Volumes consumed are small relative to other applications, and the replacement cycle for control rods is measured in years rather than months. However, this is a genuinely non-substitutable indium use: the specific nuclear properties and material behaviour of the In-Ag-Cd alloy under reactor conditions cannot be replicated by lower-cost alternatives. As PWR capacity expands — particularly in China, India, and Eastern Europe — this application provides a stable baseline of demand.

8. Infrared Optics and Thermal Imaging Detectors

Indium antimonide (InSb) and indium arsenide (InAs) are compound semiconductors used as detector materials in infrared imaging systems. InSb focal plane arrays operate in the mid-wave infrared (MWIR) band, making them the standard detector for military thermal imaging, missile guidance systems, and scientific instruments. InAs is used across a broader infrared spectrum including shortwave and mid-wave applications.

Defence procurement is the primary demand driver. Key manufacturers include FLIR Systems (now part of Teledyne Technologies), Leonardo DRS, and Lynred (France). This application is supply-chain-sensitive: indium for defence-grade infrared detectors is typically sourced from Western-qualified suppliers rather than Chinese refiners, given end-use restrictions. It is a small-volume, high-value segment with structurally stable demand tied to defence budgets.

9. Battery Anode Additives and Zinc-Indium Cells

Indium is under active investigation as an anode additive in next-generation lithium-ion and solid-state batteries, where small quantities (typically below 1% by weight) can suppress lithium dendrite formation and improve cycle stability. Research groups at Stanford, MIT, and Samsung SDI have demonstrated indium-doped anodes with meaningfully improved capacity retention. Commercial deployment remains pre-scale, but battery chemistry is one of the few areas where new primary indium demand could emerge at volume.

Separately, zinc-indium anodes serve as a mercury-free alternative in alkaline primary batteries, replacing amalgamated zinc in applications where mercury content is regulated. This is an established application at low volumes. Both battery-related uses are currently a rounding error in global indium demand, but the solid-state battery pathway merits monitoring as the technology approaches commercialisation.

10. OLED Transparent Electrodes and Emerging Display Technologies

ITO is the established transparent electrode in OLED displays, maintaining its dominance from LCD into the next generation of display technology. As OLED penetration increases in premium smartphones and televisions — driven by manufacturers including Samsung, LG, and Apple — ITO demand tracks display area rather than switching technology. The structural ITO demand picture for displays therefore remains stable even as LCD and OLED coexist.

Longer term, alternative transparent conductive materials including indium zinc oxide (IZO), aluminium-doped zinc oxide (AZO), carbon nanotube films, and graphene-based coatings are being developed as potential ITO substitutes. None has yet achieved the combination of electrical performance, optical clarity, and processability required for mass production display substrates. ITO substitution remains a structural headwind for indium demand that is real but not imminent at scale.

Summary: Top 10 Indium Uses by Application

The Outlook for Indium Uses

The medium-term indium demand picture is anchored by ITO, which will remain the dominant use by volume for as long as glass-substrate display production continues at scale. Secondary indium — recovered from ITO manufacturing scrap and end-of-life panels — is increasingly meeting a portion of this demand, particularly in Japan and South Korea, which reduces pressure on primary supply. The two genuine volume growth stories are CIGS solar, if deployment accelerates beyond current niche positioning, and InP semiconductors, where 5G infrastructure and data centre interconnect investment provides a structural tailwind.

The strategic risk for indium supply lies in its by-product nature: output is constrained by zinc smelting economics, not by indium price signals. China, South Korea, and Japan account for the majority of refined indium production, with limited Western primary capacity — a supply structure that has drawn regulatory attention as part of broader critical minerals policy. For context on how indium fits within export control frameworks, see top 10 China export control minerals. Indium shares supply chain characteristics with gallium and germanium — all three are by-product critical minerals with high China refining concentration and limited Western substitutes.

This article is for informational purposes only and does not constitute investment advice.