| Item | Technical Property | ||
|---|---|---|---|
| Pure nitrogen | High purity nitrogen | Ultrapure nitrogen | |
| Nitrogen (N2) purity (volume fraction)/10-2≥ | 99.99 | 99.999 | 99.9999 |
| Oxygen (O2) content (volume fraction)/10-6≤ | 50 | 3 | 0.1 |
| Argon (Ar) content (volume fraction)/10-6≤ | - | - | 2 |
| Hydrogen (H2) content (volume fraction)/10-6≤ | 15 | 1 | 0.1 |
| Carbon monoxide (CO) content (volume fraction)/10-6≤ | 5 | 1 | 0.1 |
| Carbon dioxide (CO2) content (volume fraction)/10-6≤ | 10 | 1 | 0.1 |
| Methane (CH4) content (volume fraction)/10-6≤ | 5 | 1 | 0.1 |
| Water (H2O) content (volume fraction)/10-6≤ | 15 | 3 | 0.5 |
The primary differentiation lies in the purity levels and allowable trace impurities. Pure nitrogen offers ≥99.99% purity (4N), high purity nitrogen provides ≥99.999% purity (5N), and ultrapure nitrogen achieves ≥99.9999% purity (6N), with strictly controlled trace levels of oxygen, moisture, and hydrocarbons.
The unit 10-6 represents parts per million (ppm) by volume. It specifies the maximum allowable volume of a specific impurity gas per million volumes of nitrogen, indicating extremely low threshold tolerances for critical contaminants.
Moisture can cause unwanted oxidation, condensation, or hydrolysis reactions in sensitive manufacturing environments. In high purity and ultrapure grades, water content is limited to ≤3 ppm and ≤0.5 ppm respectively to prevent contamination in precision operations.
Ultrapure nitrogen is essential for semiconductor manufacturing, advanced electronics fabrication, photovoltaic processing, and carrier gas applications in analytical instruments where even sub-ppm impurities can damage components or distort measurements.
Argon is an inert noble gas that behaves similarly to nitrogen in most general and industrial purging applications, making its trace presence harmless. However, for ultrapure applications such as sensitive wafer processing, argon must be strictly monitored and kept ≤2 ppm.
