Pressure measurement in the Semiconductor Industry


There are 2 technologies being used in semiconductor mass flow measurement:

• Thermal distribution

• Differential pressure

Semicon pressure variation

Both measurements are pressure sensitive. It means a change in applied pressure will affect the mass flow measurement accuracy. Device makers are using independent pressure sensor to compensate mass flow measurement error induced by applied pressure. It seems that current trend is integrating pressure sensor to mass flow meter or mass flow controller. It is claimed as pressure insensitive mass flow meter or mass flow controller.

The advantage of using pressure sensor in MFC is the response:

With differential pressure measurement, the MFC can achieve the set/targeted mass flow much faster than thermal distribution measurement.

In differential pressure MFC, PID control can be used during flow increase ①, steady state ②, and flow decrease ③.

While in thermal distribution MFC, PID control can only be used during flow increase①.


Semiconductor Infrastructure: Learn how Druck helps chip makers achieve the highest reliability in the industry.
Avoid overheating with pressure sensors

Laser needs N2 gas control and the protection of heating up coming from laser beam should be supported by pressure sensors, such as Druck TERPS8100, a standard pressure sensor to major lithography tool maker companies around the world.

Deposition (CVD)
Controlling Chemical Vaper Deposition 

Deposition process, also known as “Chemical Vaper Deposition”, needs controlling many kinds of gases flow rate (AlCl3, WF6 for IC and GaNfor LED), but it’s mostly used as MFC supported by Thermal MFC without pressure sensors.

However, there is the subject kinds of accuracy at high temp in case of thermal MFC without pressure sensor.

ADROIT6200 provides the accuracy needed for this application.

Dry Etching
Solutions that support the process

Precision is key in the dry etching processes for the semiconductor industry. Different uses of dry etching make up the largest subsystem process during chip fabrication.

Druck solutions can be used in different ways during this process to help control pressure in the mass flow controller (MFC) and gas box systems to achieve very accurate gas flow control.

Main applications are: MFC for dry etcher and Gas box system for dry etcher

Chemical Mechanical Polishing (CMP)
Zero reset solutions

During this part of the process the wafer material is planarized to smooth surfaces through a combination of chemical and mechanical forces. The head of the polisher system needs to be calibrated and maintained in a way that produces fast and repeatable results for each wafer that passes through this process.

Our UNIK5000 configurable sensor coupled with Druck's Pressure Indicator and Loop Calibrator is ideal for constant control of pressure sensor applications to achieve consistent results during this process.