How to configure clean air supply in the maintenance area of ​​thin film deposition equipment?

Maintenance of thin film deposition equipment requires opening the chamber, disassembling components, and replacing consumables. Exposed parts in maintenance areas may include cleaned surfaces, spare parts, and reassembly locations. These components are sensitive to particles, and the air environment in the maintenance area will affect the quality of maintenance.

However, the maintenance area may also contain equipment residues, process by-products or hazardous materials. Clean air supply can only be used as part of maintaining the environment and cannot replace isolation, exhaust and personnel protection. To configure clean air supply, you need to first clarify the maintenance tasks and the nature of the pollution.

Identify maintenance tasks and exposed parts

Before configuring clean air supply, first confirm what tasks need to be completed in the maintenance area:

• Open the cavity and remove parts;

• Clean the inside of the cavity;

• Replace consumables and spare parts;

• Reassembly and calibration;

• Temporarily store cleaned parts.

Different tasks correspond to different exposed parts and contamination risks. Cleaned surfaces and spare parts require particle protection, while disassembled contaminated parts require isolation. Both types of components should not be mixed in the same area.

Distinguish between clean and contaminated parts

The parts in the maintenance area have two states: clean parts and contaminated parts to be processed. Clean air supply should prioritize protecting clean parts and reassembly locations.

During inspection, you should confirm:

• Temporary storage location for cleaning parts;

• Whether the cleaning parts are within the air flow protection range;

• Whether contaminated parts are far away from clean parts;

• Whether different areas or directions are used for disassembly and assembly.

If clean parts are placed downstream of contaminated parts, airflow may carry contamination to the clean surface. For the relationship between component placement and airflow direction, please refer to Will stacking items on the workbench create a pollution dead zone? , to understand the impact of occlusion on airflow.

The airflow in maintenance status is different from that in production status

When the equipment is opened during maintenance, the chamber boundaries and airflow paths change. Qualified airflow conditions in production conditions may no longer be applicable in maintenance conditions.

The following should be considered separately when configuring:

• Production status: The equipment is shut down and the air flow runs according to the designed path;

• Maintenance status: equipment is turned on, personnel operate, air flow path changes;

• Recovery status: Maintenance completed, verification resumed after the device was shut down.

The protection scope of maintenance status may need to be set separately. For airflow planning in closed equipment cavities, please refer to How to plan clean air supply for closed equipment cavities? , to understand the airflow organization in the open state.

Handling of residues and hazardous substances

Thin film deposition equipment may retain process by-products or hazardous materials. When such residues are involved in the maintenance area, they should be handled according to process safety requirements and cannot be dealt with only by clean air supply.

Need to confirm:

• the nature of the residue and handling requirements;

• Whether dedicated exhaust or isolation is required;

• Protection requirements for maintenance personnel;

• Maintain waste disposal procedures.

Clean air supply cannot replace dedicated exhaust, isolation or personnel protection. When hazardous materials are involved, reference should be made to Can an open workbench be used for hazardous materials operations? , do a risk assessment first.

Local air supply configuration and filtration level

The local protection of the maintenance area can be configured with equipment-side EFU, and the structure is selected according to the maintenance tasks and space conditions. The level of filtration should be determined based on the sensitivity of the exposed parts.

Please refer to the equipment side supporting EFU equipment end fan filter unit , the filtration level can be understood HEPA vs ULPA filters , check efficiency, size and installation seal. Please refer to the room background air supply FFU clean air supply products , the logic of division of labor between the two is The division of labor between device-side EFU and room FFU is explained in detail.

Recovery verification after maintenance

After maintenance is completed, the equipment is shut down and put back into operation. At this point you should confirm:

• Whether the air supply path is restored;

• Whether the filter seal is intact;

• Whether the particles inside the equipment are restored;

• Whether the maintenance process introduces contamination.

To restore verification after maintenance, please refer to What should be checked when cleaning equipment is accepted? , understand the installation status and seal inspection requirements. To determine the operating status of the equipment during acceptance, please refer to Which equipment should be in operation during acceptance?。

Project judgment example

When the maintenance area of ​​a certain thin film deposition equipment is opened for maintenance, the cleaned spare parts are placed on the maintenance table. The original plan did not provide partial protection for the temporary storage location of spare parts, and particles appeared on the surface of the spare parts. Adjustment method: Increase local air supply at the temporary storage location of spare parts to keep the cleaning parts within the air flow protection range. Spare parts particles have been reduced after adjustment.

The maintenance area of ​​another project involves process residues, and the original plan only configures clean air supply. The assessment found that the residue required dedicated exhaust treatment. Adjustment method: Increase exhaust and isolation measures, and clean air supply is only used to protect clean parts. After adjustment, maintenance safety and component protection are met at the same time.

These two situations illustrate that the clean air supply in the maintenance area should be configured according to the maintenance tasks and the nature of the pollution, and the protection of clean parts and the handling of hazardous materials need to be arranged separately.

Key points for selection and acceptance inspection

Aili industrial equipment supporting support

The clean air supply in the maintenance area of ​​thin film deposition equipment needs to be configured according to the maintenance tasks, exposed parts and the nature of the pollution. Aili Industrial has collaborative capabilities in fans, motors, filters, control systems and complete machine assembly links. It can check the EFU configuration, air supply direction, filtration level and recovery conditions based on the maintenance area space, cleaning parts location and air flow protection requirements, helping to connect the local protection and safety requirements of the maintenance area. Device side supporting can be viewed EFU equipment end fan filter unit , please refer to the filter package. HEPA and ULPA filters , please refer to room air supply FFU clean air supply products。