Real-time process gas monitoring system

Real-time process gas monitoring system pgaTOF EI-TOFMS

TOFWERK Real-time process gas monitoring system is a solution that uses the electron ionization time-of-flight mass spectrometer (EI-TOFMS).
Through many years of research and development at semiconductor manufacturing sites, we have realized visualization of semiconductor processes by monitoring all substances, which was not possible with conventional RGA gas analyzers (QMS: Quadrupole Mass Spectrometers).
Detects all precursors, by-products, and ultra-trace chemical species and enables on-demand response. Ultra-fast, highly sensitive, and robust real-time process gas monitoring improves yield and optimizes gas consumption in process chambers. It also greatly improves productivity.

About TOFWERK

TOFWERK AG is a manufacturer specializing in TOFMS (Time-Of-Flight Mass Spectrometer), established in 2002 and based in Thun, Switzerland.
Based on our TOFMS, we provide innovative solutions to support researchers and industrial customers around the world.

Features of the real-time electron ionization mass spectromete

Integrated process characterization and monitoring system

Using electron ionization time-of-flight mass spectrometry, simultaneous detection of all precursors, byproducts, and trace levels of materials enables immediate process control actions.
Provides process control and analysis information for deposition, etch, and lithography.

Compatible with various semiconductor applications

RHS monitoring, endpoint detection, plasma diagnostics, process optimization.

Ultra-fast and highly sensitive mass spectrometry monitoring

TOF mass spectrometer allows real-time monitoring of all processes with isotopic mass resolution levels at sub-second refresh rates.

Wide dynamic range

The dynamic range of 10e5 to 10e6 allows simultaneous detection of precursors, byproducts, and trace level substances.

Robust and portable

Achieve in-situ measurements with rugged and flexible equipment configuration.

Long term stability

Maintenance-free and stable continuous measurement for more than 3 months is possible.

Powerful software

Simple control interface with API for system integration.

Background reduction with notch filter technology

Control mass spectral interferences by attenuating specific ions.

Q-MS (quadrupole mass spectrometer) vs TOF-MS (time-of-flight mass spectrometer)

Typical mass spectrometers that detect gas components include quadrupole mass spectrometers and time-of-flight mass spectrometers. The features and use cases of these analyzers is shown at here.

Q-MS

Only one ion with one mass-to-charge ratio is measured per unit time.
Here, selected ion monitoring is performed to measure three ions (blue, yellow, and gray) with small mass-to-charge ratios, and the largest red ion is unmeasured. Although Q-MS is effective for measuring limited components, it is not suitable for real-time monitoring of multiple components (or non-targeting).

TOF-MS

The Extractor imparts the same kinetic energy to all ions, and they move into the TOF chamber. Reflectron improves resolution, the detector counts how many ions reach as a function of time, every ion has a flight time measured in nanoseconds, and thousands of flights add up to one report measurements.

Full-spectrum and scanning

Q-MS can count only one ion of a single m/z per unit time; in contrast, TOF-MS can count ions of all m/z in each measurement.
A full Q-MS scan requires a certain residence time for each ion, which takes a considerable amount of time, resulting in very slow measurements and a lot of information loss.
TOF-MS' ultra-high speed, high sensitivity, and huge amount of information make it possible to perform detailed process gas monitoring. Controlling gas consumption through visualization of the cleaning process and improving yield through real-time abnormality detection through process monitoring can dramatically reduce total costs. As a result, it also contributes to reducing environmental impact and enables reliable implementation of ESR.

Simultaneous measurement of all masses

Multi-element analysis for ALD (Atomic Layer Deposition) process optimization

Figure.1 shows a）the total measured mass number, and b）an expanded view of the m/Q10~80 range

Figure.1 Bi-product confirmation by multi-element analysis

Confirmation of all products and by-products in a process

Figure.2 shows a） total measurement time and b） an expanded view of 175 seconds from the start of measurement.

Figure.2 Grasp the valve control through process visualization

Reduce the recipe development time with process visualization

Figure.3 Monitoring changes in etch products due to O2 flow rate

Specification