Application of special gas tion
The gases used in the production of display screens are mainly divided into two categories: electronic special gases and electronic bulk gases. Electronic special gas mainly refers to silane, sulfur hexafluoride, nitrogen trifluoride, ammonia gas and phosphide mixture, accounting for 52% of the production of gases used; The electronic bulk gases are helium, nitrogen, oxygen, hydrogen, carbon dioxide and argon, accounting for 48% of the gases used in the manufacture.
Silane: SiH4 is one of the most critical gases in the manufacture of display screens. It is used in combination with ammonia gas (NH3) to form a silicon nitrite layer for A-SI transistors; it is used in combination with nitrogen (N2) to form A-SI preexcimer laser annealing for LTPS transistors; or it is used in combination with nitrous oxide (N2O) to form A silicon oxide layer for MO transistors.
Nitrogen trifluoride: Judging from the consumption and use amount in the production of A-SI and LTPS display screens, NF3 is the single electronic material used most in the production of A-SI and LTPS display screens, while the use amount in MO production is not as good as N2O. NF3 is used to clean PECVD Chambers. For this gas, scalability is required to establish the required cost advantage in a competitive market.
Nitrous oxide: BOTH LTPS and MO display screen are used in the production. From the perspective of consumption and consumption in the production of MO, N2O has surpassed NF3 to become the most used electronic material in the production of MO. N2O is a regional and local product. Due to its low cost, it cannot adopt a long supply chain with high logistics cost. On average, every 5.5 square meters of plain glass weighs about 2 kilograms, and it generally takes 240 tons of N2O per month to produce a 120K 8.5 MO display. The largest N2O compressed gas trailer can only provide 6 tons of N2O at a time, which is expensive and risky for MO production.
Nitrogen: Nitrogen requirements can be up to 50,000 Nm3/ h for conventional large display plants, so the on-site generator (such as Linde Metro-N ®50,000) is a cost-effective solution that reduces CO2 (carbon dioxide) emissions in display manufacturing by 8% compared to conventional nitrogen plants.
Helium gas: Helium gas is used to cool glass during and after the process. Because helium is a non-renewable gas, manufacturers are looking into reducing its use because of its cost and availability.