Concentration measurement
in the
semiconductor industry
in the
semiconductor industry
Concentration monitoring for semiconductor processes – for efficient production, stable processes, and highest quality.
Up to ±0.02 wt%
Real-time measurement
Maintenance-free
Cost-saving
Challenges in concentration measurement in semiconductor processes
In semiconductor manufacturing, the exact ratio of chemical concentrations is crucial, but classical laboratory analyses often deliver results too late. With LiquiSonic® SensoTech enables reliable real-time monitoring that can be easily integrated into existing processes. The system delivers precise measurement data maintenance-free, thus enhancing process safety and efficiency.
Challenges
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Chemical concentrations not within the target range
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Time-consuming laboratory analyses
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No immediate and reliable information on chemical composition
Solution: LiquiSonic®
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Clear monitoring with LiquiSonic®
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Immediate display of chemical concentration
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Seamless integration into existing systems
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Maintenance-free and without consumables
Your advantages
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Traceable and reliable measurement results
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Measurement results in real-time
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Completely maintenance-free sensors and chemical-resistant materials
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Easy integration into systems of any size and configuration
Our solution: The LiquiSonic® measurement system
Monitor concentration in real-time
LiquiSonic® kombiniert moderne Ultraschalltechnologie mit temperaturkompensierter Messung, um präzise Ergebnisse bei kritischen Chemikalienmischungen in the Halbleiterfertigung zu liefern. Die Echtzeitüberwachung sorgt für eine stabile Produktqualität, reduziert Abweichungen und stellt Daten für Prozessoptimierungen bereit. Dadurch sinken Betriebskosten und Chemikalienverbrauch, während Prozesssicherheit und Effizienz steigen.
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Ensure quality: Real-time monitoring guarantees precise results without deviations.
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Reduce costs: Optimized processes for maximum reliability and lower consumption.
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Increase efficiency: Higher product quality with reduced operating costs.
Technical details and specifications
Ultrasonic measuring principle
The speed of sound in liquids is directly related to the concentration of dissolved substances. High-precision time measurements enable exact determination of the concentration.
Conductivity integration
In three-component systems, conductivity is used as a second physical parameter to clearly determine both concentrations.
Temperature compensation
Two PT1000 sensors integrated into the measuring cell provide automatic temperature compensation, ensuring precise measurements under all conditions. By directly capturing the process temperature, the speed of sound is corrected in real time, improving stability and accuracy even with fluctuations.
Economic benefit
Real-time concentration measurement increases quality, efficiency, and reliability, while simultaneously reducing costs and resource consumption:
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Reduced operating costs due to lower chemical consumption and fewer laboratory analyses
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Less scrap and rework, as deviations can be immediately detected and corrected
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Stable product quality ensures competitiveness and reduces complaints
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More efficient processes through real-time data instead of delayed laboratory measurements
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Higher plant availability through maintenance-free sensors without consumables
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Process optimization through precise data leads to continuous improvement and better resource utilization
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Fast ROI thanks to savings on energy and operating costs
Technical specifications
Measurement accuracy | Up to ±0.02 wt% |
Temperature range | 5 °C to 60 °C |
Pressure range | Up to 4 bar |
Material & coating | PFA |
Digital transmission | Up to 1,000 m (more on request) |
Interfaces | 4-20 mA, Profibus, Ethernet, Modbus, Fieldbus, ... |
Protection class | IP65 |
Calibration | One-time factory calibration |
Maintenance | Completely maintenance-free |
Application examples
Typical chemical process steps and our process solutions used for them process solutions for cleaning and etching processes as well as special etching and development processes:
SC-1 (APM)
NH4OH/H2O2
SC-2 (HPM)
HCI/H2O2
SPM (Piranha)
H2SO4/H2O2
Oxide Removal (DHF)
HF
Oxide Removal (BOE/BHF)
HF/NH4F
Si₃N₄ Etching
H3PO4
Isotropic Silicon Etching
HF/HNO3
Anisotropic Silicon Etching (MEMS)
KOH/Si
TMAH/Si
Photoresist Development
TMAH
Nitric Acid / Acetic Acid
HNO3/CH3COOH
HF / HCl
HF/HCl
Success Stories and References:
Detailed case studies and customer references are available from our sales team. Contact us for specific application examples from your industry.
Key Benefits at a Glance
Consistent Quality
Real-time monitoring prevents deviations and ensures consistent product quality.
Cost Savings
Reduced chemical consumption and lower operating costs through optimized processes.
Highest Efficiency
Real-time data enables faster decisions and optimized processes.
Maintenance-free
Sensors are chemical-resistant and require no consumables.
Frequently Asked Questions
SensoTech GmbH ist ein führendes Company im Bereich der Prozessmesstechnik mit Sitz in Barleben, in der Nähe von Magdeburg, Deutschland. Wir entwickeln und produzieren innovative Lösungen zur Überwachung und Optimierung industrieller Prozesse. Unsere Spezialisierung liegt hierbei in der präzisen Messung von Konzentrationen, Dichten und anderen Parametern in Flüssigkeiten - in Echtzeit und direkt während des Prozesses.
Unlike optical methods, which are influenced by color or turbidity, conductivity-based methods, which are sensitive to electrical conductivity, or density-based methods, which can be disturbed by temperature or gas bubbles, our ultrasonic method is independent of these influences.
The LiquiSonic® measurement technology also contains neither moving parts nor components that can wear out or be consumed. Therefore, after installation, the measurement system is completely maintenance-free and drift-free.
The sensors offer digital signal transmission up to 1000 m and enable continuous inline measurement without sample extraction.
Unser System nutzt die Ultraschall-Laufzeitmessung zur Bestimmung der Schallgeschwindigkeit in Flüssigkeiten. Diese Schallgeschwindigkeit korreliert direkt mit der chemischen Konzentration und ermöglicht measurement accuracies of up to ±0.02 wt% für die Halbleiterindustrie. Die integrierte Temperature compensation gewährleistet stabile Ergebnisse auch bei schwankenden Prozessbedingungen.
The system delivers results in real time. It performs over 30 measurements per second. Based on these measurements, you get an up-to-date measurement value every second. This fast response time enables effective process control and early detection of deviations.
Our semiconductor sensors operate reliably in a temperature range from 5 °C to 60 °C and pressures up to 4 bar.
Yes, by combining sound velocity measurement with additional physical quantities (e.g., conductivity), multiple components gleichzeitig bestimmt werden. So lassen sich auch weitere Zusatzstoffe in the Halbleiterfertigung überwachen.
Das Halbleiter-measurement system ist completely maintenance-free. Es gibt keine mechanischen Verschleißteile, Dichtungen oder optische Fenster, die angegriffen werden könnten. Eine regelmäßige Calibration ist nicht erforderlich - die LiquiSonic® Sensoren bleiben über Jahre stabil.
The system offers various digital interfaces (e.g., Profibus, Ethernet/IP, Foundation Fieldbus) as well as analog 4-20 mA outputs. The Integration erfolgt problemlos via standardized protocols.
Da die Schallgeschwindigkeit von der Temperatur beeinflusst wird, sind unsere LiquiSonic® Sensoren mit hochpräzisen Temperatursensoren ausgestattet. So kann der Einfluss der Temperatur auf die Messung directly compensated werden. Daher ist es nicht nötig, zusätzliche Temperatursensoren in den Halbleiterprozess einzubinden.
Related applications
Texture and etching baths
In etching baths, material layers are selectively removed to create desired surface structures.
PCB cleaning
Cleaning removes organic residues, particles, and oxides to ensure reliable processing of the circuit paths.
Pickling bath monitoring
Pickling baths dissolve oxides or impurities from metal surfaces and must be kept at the correct concentration range.
Green liquor monitoring
Green liquor is a highly alkaline byproduct in paper manufacturing, and its concentration must be monitored for stable subsequent processes.
Acid concentration measurement
The precise determination of concentrations in aggressive chemicals is crucial to allow reactions to proceed in a controlled and safe manner.
Gas scrubber
In gas scrubbers or neutralization plants, pollutants are removed from exhaust air or liquids, requiring precise control of the chemicals used.