Process Control and Contamination Monitoring with RGAs

Residual gas analyzers (RGAs) are compact quadrupole mass spectrometers that are commonly used for process control and contamination monitoring in ultrahigh vacuum (UHV) applications. RGAs are developed and manufactured using differing ion source components and pressure differential sampling systems, but the basic setup depends upon a probe equipped with an ionizer and a sensitive detector capable of measuring the resolution of mass-to-charge ratios. Using this methodology, it is possible to quantify residual gases or vapor in a vacuum and vacuum process with minimum alteration to the chemistry of the vacuum environment.


Hiden Analytical RGAs are routinely used to perform control or monitoring tasks such as:

  • Vacuum diagnostics including leak detection, where a gas such as helium (He) measured at mass 4 is used as a search gas for rapid analytical responses;
  • Quality measurement and monitoring for research vacuum chambers and vacuum furnaces, where outgassing of hydrogen (H2) measured at mass 2 can hinder achievement of ultimate vacuum conditions;
  • Contamination detection, where various hydrocarbons are used in highly sensitive broad mass scans to diagnose the contamination levels of a UHV chamber.

Hiden’s RGA Series features RGAs at three specification levels: the HALO; the 3F Series; and the 3F-PIC. Each one is calibrated and tested to ensure exceptional performance levels with ultimate degrees of accuracy, and varying components for alternative specifications. This precise series of mass spectrometry instruments feature mass range options of 50, 100, 200, 300, and 510 amu with high-speed acquisition of data ranging to 650 measurements per-second. While the 3F series and the 3F-PIC RGAs are enabled for a broad array of analytical and research purposes, the HALO is primly suited for process control and contamination monitoring.


HALO RGAs can perform partial pressure value measurements across the mass range for multiple species monitoring in real-time, with high sensitivity. It can detect helium in air at 5 parts-per-million (ppm), which is five times better than a conventional analyzer – providing unparalleled leak detection accuracy, thus helping users to improve UHV quality in their vacuum chambers.

It is capable of trend analysis and comprehensive vacuum surveys, with a contamination resistant ion source shroud and total elimination of zero blast baseline drift. This allows for minimally invasive analysis of various species of residual gas in a UHV chamber.

We also feature an integrated process and residual gas analyzing system known as the HPR-30, which is optimized for gas and vapor analysis in a broad range of processes.

HPR-30 System

The HPR-30 System allows for direct analysis with an improved sensitivity of 100 parts-per-billion (ppb) and a broad pressure range of 10-4 – 1000 mbar. This provides incredible accuracy for process control and contamination monitoring in applications such as atomic layer deposition (ALD) and vacuum coating, where absolute degrees of purity must be maintained to ensure the accurate deposition of high-functioning nanostructures.

RGAs from Hiden Analytical

Hiden Analytical are leading specialists in the development and manufacture of dedicated mass spectrometers for a potentially limitless range of applications, informing studies and ensuring high-sensitivity process control for various sectors. Our RGAs have been implemented in various sectors, including theoretical astrochemical studies discussing the density of gaseous particles in vacuum environments.

If you would like any more information about our RGAs for process control and contamination monitoring, please do not hesitate to contact us.