The design standards for semiconductor cleanrooms typically include the following key aspects:
- Cleanroom Classification:
Adherence to international standards such as ISO 14644-1, which defines cleanroom classifications based on the number and size of particles permissible per cubic meter of air. Common classifications for semiconductor cleanrooms are ISO Class 1 to ISO Class 5.
Utilization of HEPA or ULPA filters to achieve the required air cleanliness levels. Airflow patterns are typically unidirectional (laminar flow) to minimize particle contamination.
Strict control of temperature, humidity, and air pressure to maintain stable conditions and prevent contamination. Typical temperature ranges are 20-23°C, with humidity levels between 40-60%.
- Material and Surface Selection:
Use of non-shedding, easy-to-clean materials for walls, ceilings, and floors. Common materials include stainless steel, epoxy-coated surfaces, and vinyl.
Implementation of gowning procedures and the use of cleanroom garments to minimize human-generated contamination. Personnel must follow strict protocols for entry, exit, and behavior within the cleanroom.
Design of cleanrooms to include necessary utilities such as ultra-pure water, specialty gases, and vacuum systems, ensuring that they do not compromise the clean environment.
- Vibration and Electromagnetic Interference Control:
Mitigation of vibration and electromagnetic interference, which can affect sensitive semiconductor processes and equipment.
- Maintenance and Monitoring:
Regular maintenance and real-time monitoring of cleanroom conditions to ensure compliance with standards. This includes particle counts, airflow measurements, and environmental parameter monitoring.
Adherence to safety standards and regulations, including fire safety, chemical handling, and emergency response protocols.
These design standards ensure that semiconductor cleanrooms maintain the high level of cleanliness and control necessary for semiconductor manufacturing.