• Extremely compact size and lightweight
  1/20^th size when compared to conventional residual gas analyzers making it easy to integrate to any system

• High performance
  Mini array of 9 quadrupoles gives excellent sensitivity at a fraction of the volume of traditional quadrupoles

• High pressure operation
  Can be used at up to 0.9Pa (7mTorr, 9 x 10^-3mbar) resulting in the reduction or elimination of expensive vacuum pumping for many applications

• Interchangeable sensor head in calibration
  The sensor heads are pre-tuned and calibrated prior to shipment allowing the user to make sensor changes in the field without the need for fine tuning or technical expertise

• Network sensors
  Up to eight sensors can be monitored by a single PC using RS-485. PC-less scan operation by external I/O is also possible.

• User friendly software
  Micropole Scanner™ 2 software allows the user to monitor partial pressures of gases in various modes e.g. trend graph, spectrum graph, bar graph.

Measurement principle

The quadrupole mass analyzer consists of an ion source, a mass ion detector. The residual gas is ionized when it collides with the thermoelectrons discharged from the high-temperature filament, and the ions that are thereby created accelerate and converge onto the mass filter.  At the mass filter, varying direct current and RF is applied to the electrodes (quadropoles), which allows the ions to be separated by mass. The separated ions are detected as electric current by the Faraday cup. The ion current is proportional to the partial pressure of the residual gas.

MICROPOLE^TM Analyzer

The feature that makes the quadrupole mass analyzer unique is the MICROPOLE^TM Analyzer (MPA); a grouping of nine quadropoles that takes full advantage of ultraprecision optical etching processing technology and glass/metal joint technology. The development of the MPA has enabled the creation of the quadrupole mass analyzer, world's smallest residual gas analyzer, while offering the same or better sensitivity as conventional, larger mass spectrometers. The analyzer is a plug-in unit. It features a sensor unit that has already been calibrated for partial pressure and offers absolute total and partial pressure measurement.　

Applications

Chamber condition monitoring

The Microople System QL Series has been used for measuring residual gases for a long time due to its compactness. In the metal sputtering process, it is necessary to reduce the partial pressure of oxygen-based gases in order to avoid oxidation of sputtered metals. Once a chamber is exposed to air for maintenance, it takes time to reduce residual gases and the quadrupole mass analyzer is suitable to check the chamber condition.

 

Plasma process monitoring

The quadrupole mass analyzer has one of the in-situ process monitoring techniques for plasma processes including etching, sputtering and dry cleaning. In the deposition process of transparent conductive oxide films by reactive sputtering, the control of oxygen-based gases is critical for both transparency and conductivity. Recent complexity of semiconductor processes require additional process monitoring tools for shortening equipment ramp-up time and detecting process abnormalities.