An introduction to gallium

Gallium demand and end-uses

Gallium has emerged as an indispensable material across various high-tech industries, driven by its unique physical and chemical properties. With a melting point of just 29.76°C, gallium can transition between liquid and solid states with ease, making it highly versatile in industrial applications. Furthermore, its ability to form wide-bandgap semiconductors, particularly when combined with elements such as arsenic and nitrogen, enhances its role in advanced electronics.

The semiconductor industry is the largest consumer of gallium. Gallium arsenide (GaAs) and gallium nitride (GaN) are the two primary compounds used in commercial semiconductor applications, collectively comprising around 98% of gallium usage in this sector. These materials enable the production of high-performance components capable of operating at elevated temperatures, voltages, and switching speeds—far surpassing the capabilities of traditional silicon-based semiconductors.

GaN, in particular, has revolutionised power management by allowing electronic devices to function with greater efficiency while reducing energy loss. This makes it an essential component in next-generation technologies, including electric vehicles, data centres, and industrial power supplies. As silicon-based technologies approach their physical limitations, the shift towards gallium-based semiconductors is expected to accelerate, ensuring sustained demand for this critical element.

Telecommunications represents another major sector driving gallium demand. The deployment of 5G infrastructure has significantly increased the need for GaN transistors, which offer superior thermal stability, higher frequency operation, and improved efficiency compared to conventional alternatives. These properties make GaN an ideal material for 5G base station hardware, where performance and reliability are paramount, and in recent years, the market for GaN radio frequency (RF) devices has expanded considerably.

Gallium-based components are playing an increasingly vital role in consumer electronics and power devices. GaN’s superior efficiency and power density make it an ideal choice for applications such as smartphone and laptop chargers, electric vehicle inverters, and data centre power supplies. As consumer electronics manufacturers seek to develop more compact, energy-efficient products, gallium’s importance within the industry is set to grow further.

High-efficiency solar cells, particularly those incorporating copper indium gallium selenide sulfide (CIGS) technology, have benefited from gallium’s unique properties, enabling enhanced energy conversion rates and extended lifespans. Multijunction photovoltaic cells, which utilise gallium arsenide, have been widely deployed in space applications, including satellite power systems and the Mars Exploration Rovers. These cells offer significantly higher efficiency than traditional silicon-based alternatives, making them the preferred choice for high-performance solar power solutions. Recent developments in gallium doping processes have also improved the durability and efficiency of solar panels, with China incorporating gallium into approximately 50% of its photovoltaic panel production.

Beyond mainstream industrial uses, gallium plays a crucial role in several niche applications. The aerospace and defence industries rely on gallium for radar systems and specialised electronics, where performance and reliability under extreme conditions are essential.

In the biomedical field, gallium compounds are being explored for their potential in cancer treatment and diagnostic imaging. Due to their chemical similarity to iron, gallium compounds can interfere with tumour growth, making them promising candidates for future medical therapies.

Gallium is also vital in neutrino detection research, with the SAGE experiment at the Baksan Neutrino Observatory.

Additionally, gallium-based alloys such as galinstan (a mixture of gallium, indium, and tin) are finding applications in medical thermometers and emerging cooling technologies for high-performance computing.

Gallium supply

The supply of gallium is a complex and specialised process, deeply intertwined with the extraction and processing of bauxite and zinc ores, from which gallium is obtained as a by-product. Unlike many other metals, gallium is not mined directly from its own ores but is extracted through proprietary methods while processing these other minerals. This unique method of production, coupled with the proprietary nature of the extraction techniques, makes it challenging to obtain precise data on gallium production volumes.

After its initial extraction, the gallium often undergoes refining processes to improve its purity. This refinement is crucial because the demand for gallium primarily stems from its application in high-tech industries, such as electronics, where it manufactures semiconductors and integrated circuits. The initial gallium extracted is usually of lower grade and needs to be refined to meet the high-grade specifications required for these advanced applications.

An essential aspect of the gallium supply chain is the recycling of scrap material. Given that gallium is a valuable resource with limited availability, recycling significantly supplements its supply. Recycling involves reclaiming gallium from the waste generated during the production and manufacturing of gallium-containing products. This contributes to the overall supply of gallium and highlights the industry's efforts towards sustainable practices by minimising waste and maximising resource utilisation.

Gallium substitution

In exploring alternatives to Gallium Arsenide (GaAs), organic liquid crystals are becoming viable in visual display technologies, challenging LEDs. Silicon-based CMOS power amplifiers compete with GaAs amplifiers in 3G cellular devices, illustrating the shift towards gallium substitutes. Indium phosphide and helium-neon lasers replace GaAs in specific infrared and visible laser applications. Silicon has emerged as a key rival to GaAs in solar cell technology, underscoring the broader trend towards alternatives. Despite this, GaAs and Gallium Nitride (GaN) remain irreplaceable in certain defence applications due to their unique attributes. However, in heterojunction bipolar transistors, silicon-germanium is beginning to substitute GaAs, reflecting ongoing efforts to find replacements for gallium-based technologies.