Compressed air for the semiconductor industry

Technical Specifications for Compressed Air Systems for the Semiconductor Industry

In the field of semiconductor manufacturing, compressed air is a key process medium and power source, and its quality is directly related to product yield and equipment stability. Based on industry characteristics and technological development trends, the technical requirements for compressed air systems in the semiconductor industry are described as follows:

1. Core application scenarios and quality requirements

1. Clean room environment maintenance

• function description: Prevent the intrusion of external particles through positive pressure control and maintain cleanliness levels (such as ISO 1).
• quality requirements：
  • Dust content: ≥0.1μm particulate concentration ≤10 particles/m³;
  • Oil content: ≤0.001mg/m³ (equivalent to ISO 8573- 10 standard);
  • Humidity: Pressure dew point ≤-70℃ to prevent condensed water from causing short circuit.

2. Gas supply for process equipment

• typical equipment: Lithography machine, etching machine, thin film deposition equipment.
• quality requirements：
  • Vibration control: compressed air supply pressure fluctuations ≤±0.01MPa to avoid displacement of precision parts of the equipment;
  • Instantaneous flow rate: Meet the peak gas demand of the equipment (for example, the instantaneous flow rate reaches 50m³/min during exposure by the lithography machine).

3. Factory service system support

• application scenarios: Pneumatic valves, material handling, waste gas treatment.
• quality requirements：
  • Water content: Pressure dew point ≤-40℃ to prevent pipeline corrosion and microbial growth;
  • Oil content: ≤0.01mg/m³ to avoid oil pollution and emission of gases.

2. System design technical requirements

1. Gas supply structure

• Three-stage filtration system：
  • Primary filtration (pre-filtration): intercept particles ≥5μm, filter element accuracy level F5;
  • Secondary filtration (precision filtration): interception of particles ≥1μm, filter element accuracy level H13;
  • Three-level filtration (activated carbon filtration): adsorbs oil and peculiar smell, and the efficiency is ≥99.999%.
• drying device：
  • Freeze dryer + adsorption dryer are connected in series to ensure that the outlet dew point is ≤-70℃;
  • Equipped with a dew point meter and an automatic drain valve to monitor and remove condensate in real time.

2. pipeline system

• material selection: Priority is given to 316L stainless steel pipes, with inner wall roughness ≤0.4μm to reduce particle adhesion.
• layout principles：
  • The main pipe flow rate is ≤15m/s, and the branch pipe flow rate is ≤8m/s, reducing pressure drop and secondary pollution risks;
  • Key gas points (such as lithography machines) are equipped with independent gas supply rings to ensure pressure stability.

3. monitoring and security

• on-line monitoring：
  • Required parameters: pressure, temperature, dew point, oil content, particulate matter concentration;
  • Data recording: Historical data is stored for ≥5 years, and API interfaces are supported to interface with MES systems.
• safety protection：
  • Equipped with explosion-proof air compressor and electrical components, suitable for Class 1 Div2 hazardous areas;
  • The emergency shut-off valve (ESD) response time is ≤1 second, ensuring rapid isolation under accident conditions.

3. Special process technical requirements

1. Extreme ultraviolet lithography (EUV)

• additional requirements：
  • The compressed air needs to pass through a low-temperature cold trap (-196℃) to remove residual hydrocarbons;
  • Equipped with bipolar activated carbon filter to adsorb molecular pollutants.

2. Chemical vapor deposition (CVD)

• additional requirements：
  • The compressed air needs to pass through a catalytic oxidation device to reduce the total hydrocarbon (THC) content to ≤0.01mg/m³;
  • The stability of air supply pressure is ≤±0.005MPa to avoid fluctuations in film thickness.

3. wafer handling system

• additional requirements：
  • Configure an air tank and a pressure stabilizing valve to ensure that the synchronization of the pneumatic clamping jaw action is ≤0.1 seconds;
  • The end filter is equipped with a self-cleaning function to reduce maintenance frequency.

4. Operation and maintenance management specifications

1. preventive maintenance：
   • The air filter element is replaced every 2000 hours, and the oil filter is replaced every 4000 hours;
   • The desiccant is regenerated or replaced every 2 years, and the adsorbent is replaced every 5 years.
2. energy efficiency optimization：
   • Through frequency conversion transformation and waste heat recovery, system energy efficiency is improved by 15%-25%;
   • Equipped with an intelligent control system to automatically start and stop the equipment according to the gas consumption.
3. Emergency Management：
   • Configure standby air compressor and dryer, automatically switch when the main system fails, and the switching time is ≤30 seconds;
   • Regularly drill emergency plans to ensure that critical equipment is safely shut down when compressed air is interrupted.

By strictly implementing the technical specifications for compressed air systems in the semiconductor industry, companies can ensure process stability and product yield, reduce quality risks, and improve the energy efficiency and reliability of production systems.