Complete Logic for Triggering Protection Parameters in Semiconductor Factories During Earthquakes

The Core Premise of Triggering Protection: Real-time Parameter Monitoring Link

During an earthquake, the triggering protection of control parameters relies on the real-time data linkage of a three-layer monitoring system, ensuring that parameter collection is complete and timely, providing accurate basis for subsequent judgments:

1. 1. Macro Seismic Wave Monitoring: A three-component seismometer (such as Advantech PCI-1747U) collects vibration acceleration, velocity, and frequency data of the factory foundation in real-time, covering a frequency range of 0.1-50Hz, with a sampling rate of up to 2048Hz, capable of quickly capturing seismic P-waves (longitudinal waves) and S-waves (transverse waves);

1. 2. Equipment-level Micro-vibration Monitoring: Vibration sensors (such as Zolix KV-3000) installed on core equipment like lithography and etching machines monitor micro-vibrations of the equipment body with a response speed of 0.1s and a resolution of 0.001g, accurately capturing the displacement caused by earthquakes;

1. 3. Environmental – Safety Parameter Monitoring: Environmental linkage modules (Advantech WISE-4000) synchronously collect parameters such as temperature and humidity, gas concentration (e.g., hydrogen, chlorine), and air pressure in clean rooms, preventing secondary environmental fluctuations caused by earthquakes from affecting protection actions.

All monitoring data is transmitted in real-time to the early warning host in the control room (Advantech DAQ-9178), with data latency <10ms, allowing time for triggering decisions.

The Core Logic of Triggering Protection: Hierarchical Threshold Determination Mechanism

The triggering of control parameters is not based on a single threshold but is based on a **“Pre-warning – Emergency Protection – Structural Protection” three-level threshold**, combined with differentiated judgment based on the sensitivity levels of different processes, with the specific logic as follows:

Protection Level	Trigger Basis (Control Parameters)	Determination Criteria (Combined with Process)	Trigger Priority
Pre-warning Trigger	Core equipment vibration acceleration, gas concentration parameters	Reaching 80% of the core equipment threshold (e.g., 0.016-0.024g for 28nm process core equipment), or gas concentration exceeding the safety threshold by 10%	1 (Earliest Trigger)
Emergency Protection Trigger	Core equipment / Auxiliary equipment vibration acceleration, velocity, response time parameters	1. Core Equipment: Reaching customized thresholds (e.g., 0.03-0.05g for 12-inch wafer production line, 0.01-0.02g for advanced processes), and response time <0.5s 2. Auxiliary Equipment: Transmission system reaching 0.08-0.1g, gas supply system reaching 0.1-0.3g	2 (Core Trigger)
Structural Protection Trigger	Foundation vibration acceleration, structural displacement parameters	Foundation vibration reaching 0.3-0.5g, or structural displacement >0.3mm (approaching 60% of recovery determination parameters)	3 (Last Trigger)

Key Note: The threshold differences for different processes directly affect the sensitivity of triggering. For example, advanced processes (≤14nm) have a vibration acceleration threshold of only 0.01-0.02g, which will trigger emergency protection earlier than auxiliary processes (0.1-0.3g), preventing damage to ultra-precision components such as EUV lens groups.

The Execution Process of Triggering Protection: Action Implementation Based on Parameter Linkage

When monitoring parameters reach the corresponding thresholds, the early warning host will link the equipment, environment, and structural systems, executing protection actions in the order of “first protect core equipment → then protect materials → finally protect structure,” with the specific process and control parameter linkage as follows:

1. 1. Pre-warning Stage (Parameter: Acceleration reaches 80% of threshold)

• Action: The control room issues an audible and visual alarm while cutting off the supply of flammable/corrosive gases such as hydrogen and chlorine (relying on pneumatic emergency shut-off valves, response ≤0.2s);

• Parameter Linkage: The vibration speed parameters of the gas supply system (≤12μm/s) are monitored synchronously. If the auxiliary equipment threshold is not reached, only the gas supply is cut off without stopping the production line, leaving a buffer for possible “false triggers.”

1. 2. Emergency Protection Stage (Parameter: Acceleration reaches core threshold)

• Action 1 (Protect Equipment): Core equipment (lithography and etching machines) immediately stops the process and seals the reaction chamber (electric sealing door IP67 rated, ensuring stable temperature/humidity/air pressure inside the chamber);

• Action 2 (Protect Materials): The wafer transfer system automatically transfers silicon wafers to shockproof storage boxes (impact resistance ≥50g) based on vibration speed parameters (≤3μm/s for core equipment), preventing wafer breakage;

• Parameter Linkage: The environmental monitoring module provides real-time feedback on temperature, humidity, and air pressure parameters (e.g., 28nm process requires air pressure fluctuations ≤±0.1kPa). If parameters are abnormal, additional inert gas replenishment actions are triggered.

1. 3. Structural Protection Stage (Parameter: Foundation acceleration reaches 0.3-0.5g)

• Action: Activate the active vibration isolation platform (six degrees of freedom control, isolation rate ≥95%), adjusting the platform vibration frequency (0.5-5Hz) to counteract foundation vibrations; simultaneously, polyurethane damping pads (base layer) absorb vibration energy through their own loss factor (≥0.35);

• Parameter Linkage: Real-time monitoring of the isolation layer transmission rate (must be ≤10%). If the transmission rate exceeds parameter standards, secondary adjustments of the platform are triggered to ensure that vibrations in the core equipment area are effectively reduced.

The Key Guarantee of Triggering Protection: Parameter Verification in the Recovery Stage

After the earthquake stops, the protection actions do not end; it is necessary to verify throughrecovery determination parametersto confirm that the equipment, environment, and structure meet the restart conditions, avoiding secondary damage due to unqualified parameters:

• Equipment Parameters: Core equipment vibration returns to ≤0.005g (12-inch production line), ≤0.001g (advanced process), equipment calibration error <0.1nm;

• Environmental Parameters: Temperature and humidity stable for more than 30 minutes, air pressure fluctuations ≤±0.1kPa, gas purity restored to 99.999%;

• Structural Parameters: Structural displacement ≤0.5mm, isolation layer transmission rate ≤10%.

Only when all recovery parameters meet the standards will the early warning host allow the production line to gradually restart, forming a complete closed loop of “monitoring – triggering – protection – verification.”

Summary: Core Characteristics of Control Parameter Triggering Protection

1. Parameter Driven: All protection actions are based on quantifiable parameters such as “vibration acceleration, velocity, response time, displacement,” avoiding delays in manual judgment;

1. Process Adaptation: The threshold differences for different processes ensure that triggering sensitivity matches the sensitivity levels of the equipment, avoiding omissions in protection and frequent false triggers;

1. Linkage Collaboration: Equipment, environment, and structural parameters are linked to avoid incomplete protection caused by single parameter triggers (e.g., only protecting equipment while ignoring gas leakage risks).