ASML 4022.635.04286 MF LS Purging Supply Assembly

The ASML 4022.635.04286 is a multifunction (MF) lens and mirror (LS) purging supply assembly designed to provide clean, dry nitrogen or clean dry air (CDA) to critical optical elements in ASML steppers. This unit filters and regulates the purge gas, removing moisture, particles, and hydrocarbon contaminants to prevent optical degradation and haze formation.

Technical Specifications

• Part Number: 4022.635.04286

• Type: Purging supply assembly for MF LS

• Gas Compatibility: Nitrogen (N₂) or Clean Dry Air (CDA)

• Inlet Pressure: 4–10 bar

• Outlet Pressure: 0.5–2 bar (adjustable)

• Flow Rate: 10–100 L/min (depending on application)

• Filtration: 0.01 µm particle filter, activated carbon adsorber, and moisture trap

• Output Dew Point: < -70°C

• Ports: 1/4 inch Swagelok fittings

• Material: 316L stainless steel and PTFE seals

Functional Description

The assembly sequentially processes incoming gas through a coalescing pre-filter, a desiccant dryer, and a final absolute filter. An integrated pressure regulator maintains a stable outlet pressure despite variations in the supply. The unit also includes a flow meter and a pressure gauge for monitoring. An optional oxygen sensor can be installed to verify the inert atmosphere.

Installation and Piping

Mount the supply assembly on a wall or inside the stepper frame using the supplied brackets. Connect the inlet gas line to the plant nitrogen or CDA supply. Use clean, passivated tubing and avoid sharp bends. After installing, purge the system for at least 10 minutes to remove air before connecting to the optical elements. Secure all connections with appropriate torque (10 Nm for Swagelok).

Operation and Calibration

Set the desired outlet pressure and flow using the regulator and needle valve. The built-in flow meter should be calibrated periodically against a reference flowmeter. The dew point should be checked with a portable hygrometer; if it exceeds -60°C, replace the desiccant cartridge. The differential pressure across the filter indicates when replacement is needed.

Maintenance and Filter Replacement

Routine maintenance involves replacing the particle filter every 6 months and the activated carbon cartridge every 12 months. The desiccant dryer can be regenerated by heating in a dry oven, but replacement is recommended. Always use clean gloves when handling filter elements. Keep a log of pressure drops and flow rates to predict replacement cycles.

Integration with Stepper Optics

This purging supply connects to the lens barrel and mirror housings of PAS 5000/2500 systems. It ensures that the optical path remains free of absorbing contaminants, thereby maintaining high throughput and image quality. The assembly can be controlled remotely via the stepper’s environmental control system.

Environmental and Safety

The assembly is designed for use with non-flammable gases and complies with ASME B31.3 piping standards. It is CE marked and meets cleanroom requirements for outgassing and particle generation. Operating temperature range is 10°C to 40°C.

Spare Parts and Support

ASML provides full kits of replacement filters, seals, and regulator repair kits. Detailed maintenance manuals and troubleshooting charts are available. Certified technicians can perform on-site calibration and performance verification.

Conclusion

The ASML 4022.635.04286 MF LS Purging Supply Assembly is a reliable and efficient solution for protecting valuable optical components. Its advanced filtration and precise control ensure long-term optical stability in high-end lithography.