Brooks Instrument presents the theory of operation behind their pressure-based mass flow controller (P-MFC) from their GP200 series in this video. This P-MFC has a unique design approach for enhanced process performance without the limitations of today's traditional P-MFCs. A traditional P-MFC system includes:
- An upstream pressure transducer.
- An upstream control valve.
- Two individual pressure transducers.
- Laminar flow element.
The use of an upstream valve has many disadvantages. This design requires high pressure making it sub-optimal for critical low-pressure gases and low full-scale flow rate. It also means matching the two individual pressure transducers perfectly.
Brooks Instrument designed a patented integrated differential pressure transducer, GP200 P-MFC, to address the disadvantages. The GP200 has one actual differential transducer instead of two, eliminating the need to match the two individual pressure transducers, significantly reducing measurement uncertainty, and improving accuracy, particularly for critical low vapor pressure process gases. Its downstream valve architecture will operate at much lower inlet pressures and across a broader range of pressures. The downstream valve also minimizes the bleed-down effect and ensures that the device is insensitive to dynamic outlet conditions.
The GP200 Series P-MFC features a patented architecture that overcomes the limitations of conventional P-MFCs to provide the most precise process gas delivery even when delivering low vapor pressure process gases. It includes several unique design aspects, including an integrated differential pressure sensor coupled with a downstream valve architecture enabling the most precise process gas delivery over the industry's broadest range of operating conditions.
Since GP200 Series supports a broad range of process conditions, it can be used as a drop-in replacement and upgrade for many traditional P-MFCs and thermal MFCs. It reduces the complexity and cost of ownership of the gas delivery system because it eliminates the need for components such as pressure regulators and transducers.
GP200 FEATURES
- True differential pressure measurement
- Lower inlet pressure operation
- Downstream valve architecture
- Matched transient response
- Zero Leak-by Control Valve
- MultiFlo™ technology offers unparalleled flexibility—one device can be programmed for thousands of different gas and flow range configurations without removing the MFC from the gas line or compromising accuracy
- Local display indicates flow, temperature, pressure and network address
- DeviceNet™, EtherCAT®, RS-485 L-Protocol and analog interfaces
GP200 BENEFITS
- By removing the requirement to match and compensate two separate pressure transducers, the GP200 differential pressure technology reduces measurement uncertainty for enhanced accuracy, repeatability and drift performance.
- Safer fab operation at lower inlet pressures is now achievable with a P-MFC due to the GP200 differential pressure sensor that is specifically optimized for low differential pressure measurement.
- The downstream valve architecture ensures accuracy is independent of downstream pressure, enabling flow delivery into pressures as high as 1200 Torr. The fast closing valve addresses non-productive recipe wait times, or "tail effects," seen in upstream MFC valve designs that require additional time to bleed down their internal volume of gas.
- Ultra-fast, highly repeatable ascending and descending flow stabilization time enables tighter process control in advanced high cycle Deposition and Etch processes.
- 100X improvement in valve shut-down
- With MultiFlo™, MFC full scale flow range can be re-scaled down typically by a factor of 3:1 with no impact on accuracy, turndown or leak by specifications, for optimum process and inventory flexibility
- Convenient user display and independent diagnostic/service port aids device installation, monitoring and troubleshooting
For more information about Brooks Instrument products, contact Miller Energy, Inc. Call 800-631-5454 or visit https://millerenergy.com.
