Electronic specialty gases: Characteristics
Why five nines of purity is just the starting point
What this tab covers The physical and chemical properties that set its grade, price and uses, with the commercial grades and the standards that define them.Purity and consistency are the product. Fabs specify gases to 5N or 6N with ppb limits on moisture, oxygen and metals, and qualify each supplier and plant. Changing source can take months of testing, which locks in suppliers.
Properties that matter commercially
| Property | Value / specification | Why it matters | Source |
|---|---|---|---|
| Purity | typically 99.999% (5N) to 99.9999% (6N) for specialty gases (indicative) | Contaminants kill yields at nanometre scales | Indicative |
| Global warming potential (100-year) | NF3 about 17,400; SF6 about 24,300; CF4 about 7,380; C2F6 about 12,400 (IPCC AR6, indicative) | Sets climate impact of leaks and unabated use | IPCC AR6 (indicative) |
| Helium grade | Grade A at least 99.997% He | Required for cooling and lithography | USGS MCS 2026 |
| Neon in laser gas | about 95-99% of ArF/KrF excimer laser mixes (indicative) | Buffer gas for DUV lithography lasers | Indicative |
Commercial grades
- Electronic grade 5N-6N specialty gases
- Bulk ultra-high-purity N2, O2, Ar, H2
- Grade-A helium
- Excimer laser gas mixes
- Isotopically enriched gases (e.g. for dopants)