Difference between controllers and meters
Although both mass flow controllers and mass flow meters are sometimes abbreviated as “mass flow,” a mass flow meter is equipped with a mass flow sensor and outputs flow, while a mass flow controller provides feedback control of a built-in control valve with PID control based on the current flow rate of the mass flow sensor.
Comparison of Mass Flow Controllers and Meters
  Mass Flow Controller |  Mass Flow Meters | |
|---|---|---|
| Purpose | Mass Flow Control | Mass Flow Measurement |
| Main parts | Mass flow sensor, control valve | Mass Flow Sensors |
| Merit | Automatic control of flow rate is possible | Low pressure loss |
| Demerit | Pressure drop is greater than that of a mass flow meter | Flow control is not possible. |
What are mass flow controllers used for?
Mass flow controllers are generally used primarily for flow control in deposition processes for semiconductors, flat panels, and solar cells. Specifically, they are used to control the flow rate of reaction gases for CVD in the front-end semiconductor manufacturing process, plasma sources for PVD, and etching gases.
However, it is used not only in the deposition process, but also in various fields that require high-precision flow control. Examples include analytical and evaluation equipment, fuel cells, combustion gas control, biotechnology, medical, food, laboratory equipment, and factory equipment. Mass flow controllers play an important role in a variety of applications where precise fluid control is required.
What is the role of the mass flow meter?
Mass flow meters measure the mass flow rate. In the case of gas, it is used to measure the totalized flow rate (amount used) of the gas used, or to measure the flow rate of gas controlled by a mass flow controller for double-checking or as a simple reference instrument. The liquid mass flow meter is also equipped with a signal to control the control valve and is used to control the liquid control valve (CV-1000) or the flow control valve built into the vaporizer.
- Gas Usage Management
- Confirmation of flow rate controlled by mass flow controller
- Flow control of liquid control valves and vaporizer control valves
