Excimer laser gas usage reduction technology for semiconductor manufacturing

ArF and KrF excimer lasers are widely used as a light source for the lithography process of semiconductor manufacturing. The excimer lasers consume laser gas mixture in a discharge chamber as laser media, and more than 96% of the gas mixture is Neon. Recently Neon supply and demand balance became critical situation; the price has risen two years ago due to the instability of politics and economy in Ukraine. Although Neon price decreased now, its price is still higher than two years ago. Gigaphoton has released gas consumption reduction, called Total Gas Management (TGM) series, as part of the green activities. Conventional gas consumption reduction (eTGM) achieved 50% gas consumption reductions from the former gas control (sTGM) by optimizing the laser gas control. In order to reduce gas consumption further, Gigaphoton has been developing new gas recycle system hTGM. hTGM purifies used gas so that laser can use it repeatedly. Field evaluation of KrF-hTGM system has been started. The system was connected to five KrF laser systems and achieved 85% of the gas recycling ratio, keeping stable laser performance. Also, internal evaluation of ArF-hTGM system has been started. The system was connected to one ArF laser and achieved 92% of the gas recycling ratio, keeping stable laser performance.