Compressed air standard for semiconductor packaging and testing industry?

In the semiconductor packaging and testing industry, compressed air is a key power source and process medium, and its quality standards are extremely strict, which is directly related to product yield, equipment life and the cleanliness of the production environment. The following is a detailed analysis of the compressed air standards for the semiconductor packaging and testing industry:

1. Core standard system

1. International standard (ISO 8573-1:2010)
   • oil content: Class 0 level must be reached, that is, the residual oil amount is ≤0.01 mg/m³.
   • water content: The dew point temperature needs to be ≤-40 ° C, and some precision processes (such as processes below 3nm) require less than-70 ° C.
   • particulate matter: Must comply with ISO 8573-2 Class 1 standard, that is, particles above 0.1μm ≤200 grains/m³.
2. Semiconductor Industry Standards (SEMI)
   • SEMI F58-0701: Specify the purity of gases and liquids, require a total sulfur content of ≤0.1 ppm, and no siloxane pollution.
   • SEMI C1.3: For wafer transfer systems, compressed air needs to pass through a high-efficiency filter (HEPA grade) to ensure dust and oil free.

II. China National Standard (GB/T 13277.1-2023)

• The ISO 8573 standard is equally used to classify the particulate matter, water, and oil content in compressed air.
• For example, the compressed air quality requirements of a semiconductor packaging and testing factory are:
  • particulate matter: 0.1μm≤200 grains/m³ (ISO Class 1)
  • dew point:-40 ° C (corresponding to water content ≤0.12 g/m³)
  • oil content：≤0.01 mg/m³（ISO Class 0）

3. Special industry requirements

1. Clean Dry Air (CDA)
   • high purity: Contains almost no dust and particles to prevent wafer contamination and short circuit.
   • low water content: Avoid moisture condensation that affects process accuracy or causes corrosion.
   • oil-free: Prevent oil from polluting semiconductor materials and equipment and affecting electrical performance.
2. critical process parameters
   • granularity: Class 100 clean rooms require ≤3520 particles>0.1μm per cubic meter of air.
   • humidity: The dew point temperature usually needs to reach-40℃ or lower (such as photolithography).
   • oil content: Total oil content (liquid oil + oil vapor) ≤0.01 mg/m³.

4. Technical realization means

1. oil free compressor
   • Use water-lubricated or PTFE coating technology to avoid the risk of oil contamination.
2. multistage filtration system
   • Activated Carbon Filter: Remove oil vapor.
   • Ultra-precision filter: The filtration accuracy reaches 0.01μm to intercept particulate matter.
3. Piping and Connections
   • Use electropolished stainless steel pipes (surface roughness Ra≤0.4μm) and weld connections to reduce leakage.
4. Real-time monitoring and traceability
   • Install dew point sensors and oil vapor detectors, and the data must comply with FDA 21 CFR Part 11 requirements.

5. Monitoring and verification

1. regular testing
   • particulate matter: Samples were collected with a laser particle counter and the particle diameters of 0.1μm, 0.5μm, and 5.0μm were detected.
   • oil content: Take samples from the oil detection box, and record it as not detected when the reading is <0.1 mg/m³.
   • water content: Measure with a dew point meter or water vapor detection tube to ensure that the dew point is ≤-40 ° C.
2. third-party certification
   • Compliance reports are issued by SGS, TÜV and other agencies to verify the quality of compressed air.
3. periodically verified
   • Oil content, dew point and particulate matter are tested quarterly, and full analysis is conducted annually.

6. Typical application scenarios

1. Wafer transfer and robots
   • Oil-free and dust-free compressed air drives the cylinder to prevent particles from scratching the wafer surface.
2. Lithography and etching processes
   • CDA is used to purge dust on the wafer surface to ensure lithography accuracy.
3. positive pressure ventilation system
   • Compressed air maintains positive pressure in the clean room to prevent external pollutants from entering.

summary

The standard for compressed air in the semiconductor packaging and testing industry covers three core indicators: oil content, water content, and particulate matter, which need to be achieved through technical means such as oil-free air compressors, multi-stage filtration, precision piping and real-time monitoring. Strict compliance with ISO, SEMI and national standards and regular third-party verification are the key to ensuring compressed air quality, ensuring production yield and equipment reliability.