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InDuct™ FTIR Gas Sensor

Part Number: InDuctProduct Details


Cost effective, compact InDuct¹ FTIR sensors are easily integrated into any process for fault detection, monitoring, control, or endpoint determination. By providing real-time, quantitative absolute and relative gas partial pressure information on numerous gas species, this sensor is ideal for process and chamber matching applications. The InDuct sensor is easily fitted with custom flanges, valves and vacuum components for OEM and end user applications - no sample handling required.

Gas concentrations can be measured from % (Torr) to ppm (mTorr) levels with only two process matched optical view ports. The InDuct requires no other proces wetted optical or electronic components and can operate at pressures from mTorr to above atmospheric without any optical modifications. The sensor acquires process data continuously without recalibration and/or zeroing for many applications. Novel electronics, software and optical design produce sensors that all have identical quantitative output. Since all analysers generate the same response for the same partial gas pressure, the sensor can be ideally used for chamber matching. In addition, the InDuct FTIR sensors are well suited for etch endpoint, as well as for fault detection and control.

¹ Patent No. 6,192,287

An example of the InDuct in a fault detection and classification application is illustrated in Figure 1 below. This plot depicts the variability of one process gas during the course of a standard wafer etch (middle) and the deviation from the standard when faults occur (upper and lower). The upper trace is a result of poor wafer chucking, the lower trace is due to a 5 sccm air leak. Figure 2 depicts the ability of the InDuct to view multiple species during an etching process.

The quantitative data for each component can be displayed graphically and numerically or passed to the process as analog or digital values. As shown in Figure 3, six gas traces are displayed simultaneously. All other gas concentrations are displayed in a data table and stored in a file. The user has full control to toggle between the time lines, current spectrum, and data table.

Click the picture for a closer look


• Torr to mTorr sensitivity for many gas species
- Including VOCs, PFCs, acids, bases, and hydrides
• Analysis of more than 30 gases
• Permanent calibration spectra reduce the need for costly gas cylinders
• Easy to install - easily fitted with custom flanges, valves and vacuum components


• Semiconductor and advanced thin film process monitoring, development, optimisation and control
- Deposition proceses, including CVD, ALD & PVD
- Etch proceses, including endpoint
- Lithography processes
• Scrubber and abatement monitoring
• Stack emissions monitoring (environmental compliance)
• Process impurity analysis
• Process exhaust


Part Number: InDuct
Computer Requirements Internal in controller. Desktop or notebook Intel Pentium® PC under Microsoft® Windows® 2000/XP and XGA display (1024 × 768) (Not required for all systems)
Recommended - Intel Pentium III, 850 MHz, Microsoft Windows 2000, 256 MB
Data Collection Time 0.3-200 sec typical
Detector TE-cooled MCT
Dimensions (L × W × H) 17.5" × 9.2" × 7" nominal; exact dimensions are application dependent
FTIR Brik™ Process FTIR
Gases and Vapors Measurable Most molecules except for N2, H2, F2 and O2
Infrared Source Silicon Carbide @ 1200°C
Installation On flange or duct with rack mountable power console
Laser Certifications Class 1 Laser Product
Measurement Technique FTIR Spectrometry
Power 100/120/220/240 VAC, 50/60 Hz, 2 Amps MAX
Pressure Transducer MKS Baratron®, 0-1000 Tor (please contact MKS for other ranges)
Purge Connection 1/8" Instant Tube
Purge Pressure 20 psig (1.5 bar) max. (Not required for all systems)
Ranges Full scale concentrations setting between <1 ppm (mTorr) and 10% (760 Torr) full scale
Scan Speed 10 scans/sec @ 2.0/cm (Detector Dependent)
Sensor Purge Flow 1.2 L/min of dry nitrogen or CO2 free clean dry air with dew points below -70°C
Spectral Resolution 2.0/cm-128/cm
Weight Sensor - 18 lbs
Controller - 20 lbs

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