Neon Recovery in Lithography
Japanese semiconductor lithography tool maker Gigaphoton has developed a novel neon gas recycling system named hTGM for its argon fluoride excimer lasers. The method has demonstrated a 50% recycling rate, with potential for further improvement through adjusted configurations. This development aims to address gaps in the chip supply chain originating from geopolitical disruptions in Ukraine, which previously supplied a significant share of the global neon used in semiconductor manufacturing, particularly for advanced DUV processes.
Following supply disruptions, manufacturing regions including China, Taiwan, and South Korea increased domestic neon production and integrated recycling systems into fabrication processes. Gigaphoton's more efficient lasers with neon recycling could further reduce material costs and reliance on international supply chains.
Other companies are also advancing this technology. Japanese environmental protection company Kanken Techno demonstrated its own neon gas recycling system for excimer lasers, achieving a recycling rate of over 90% and indicating substantial room for process optimization.
Scarcity and Supply Chain Shifts
Neon is an inert noble gas with a low boiling point and limited bonding ability, making it relatively scarce in the Earth's atmosphere. It is obtained primarily through the fractional distillation of super-cooled air as a byproduct of other industrial processes. Historically, steel-mill air-separation units in Ukraine produced crude neon before regional conflicts halted exports.
The shutdown of Ukrainian neon refiners prompted an immediate global response across major semiconductor-producing nations.
South Korea accelerated domestic production and initiated a national neon recycling program focused on in-fab recovery. Taiwan installed purification systems in existing blast-furnace air-separation units to develop a domestic supply chain targeting self-sufficiency.
China integrated neon purification into its industrial base, combining it with steel and petrochemical facilities. The United States also initiated new production facilities at Gulf Coast hubs, though domestic supply impacts are anticipated later in the decade.
Lithography accounts for approximately 70% of global neon consumption, chiefly in advanced DUV processes rather than EUV lithography, which relies on tin-plasma lasers. With DUV-produced semiconductor supply expanding alongside infrastructure buildouts, stable neon access remains a critical component of global electronics manufacturing.
Recycling Systems and Efficiency
For fabrication plants unable to control primary supply sources, recycling offers a direct countermeasure. Initial neon recycling systems were qualified for Cymer excimer ArF lasers, with major memory makers like Samsung and SK Hynix adopting recovery measures.
Gigaphoton has extended its established krypton fluoride laser recycling capabilities to ArF lasers. The company states that a single hTGM unit for ArF can reduce annual neon consumption by up to 470 kiloliters, lowering material costs and supply chain vulnerability.
However, a 50% recovery rate aligns with efficiency levels demonstrated by Cymer's recovery systems as early as 2015, and past testing indicated potential peak recovery exceeding 90%.
This suggests recovery efficiency can be scaled up, particularly as competing firms like Kanken Techno pursue certification for systems with over 90% efficiency.
Future Alternatives to Neon
While recycling mitigates immediate shortages, the semiconductor industry's long-term reliance on neon may decrease as manufacturing techniques evolve.
EUV lithography enables complex chip architectures without requiring neon gas in excimer lasers. Additionally, alternative manufacturing technologies are under development to produce DUV-equivalent light without noble or toxic gases.
Solid-state laser technologies and nanoimprint lithography show potential as alternatives to traditional DUV processes, though power thresholds and cost reduction hurdles remain.
Overcoming performance and integration challenges could eventually reduce the semiconductor industry's dependence on international neon sources, combining recycling systems with next-generation manufacturing methods.
