Measuring Concentrations of Developing Solutions and Fluoric Acid

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In a semiconductor plant, a variety of chemicals are used in various manufacturing processes. The chemicals used for specific purposes are produced by diluting raw liquid with demineralized water using in diluting equipment, and the control of the concentration at this point is performed by conductivity measurement. The ISC202 and ISC402 Inductive Conductivity Analyzer are capable of high-precision measurement, and their toroidal probe ISC40 is sealed in rugged PEEK (Poly Ether Ether Ketone) material to withstand the harshest applications. A highly reliable measurement is achieved by using ISC202/ISC450 in the control of concentrations of chemicals in a dilution system. The ISC202 and ISC450G Inductive Conductivity Analyzer also play a role in the drainage control and the processing of solutions delivered from various manufacturing processes.

Dilution System Diagram

Dilution System Diagram

Expected Benefits

  • Easy control of fluoric acid concentration
  • Reduces operating costs
  • Establishment of corrosion-resistant wetted parts

Process Overview

Up to now, chemicals used in semiconductor plants have been purchased in concentrations diluted beforehand by the chemical company to suit specific applications. However, as the price competition in the semiconductor market is increased, the operating cost reduction is highly required. As a result, each chemical used in a manufacturing process has been reviewed so that the substance profits and widespread cost reductions are secured.

Ordering chemicals in various concentrations from chemical manufacturing companies has been replaced by the installation of dilution systems at individual companies, whereby a raw chemical solution, whose price is not significantly different from that of diluted chemicals, is diluted to the required concentration, using inexpensive demineralized water.

Solution Details

Measurement system
2-wire inductive conductivity system
Sensor ISC40G(J)-GG-T1-X☐/Z Z: Teflon coating
Flow-through type holder ISC40FF(J)-PJ/Z Z: Teflon coating
Analyzer FLXA21-D-P-S-AA-C5-NN-A-N-LA-N
Dedicated distributor for transmitter PH201G-A☐*B
4-wire inductive conductivity system
Sensor ISC40G(J)-GG-T1-☐☐/Z Z: Teflon coating
Flow-through type holder ISC40FF(J)-PJ/Z Z: Teflon coating
Converter ISC450G-A-☐

Field Data

Measurement Examples

Measurement Examples


ISC202G inductive conductivity transmitter
Power supply voltage: 17 - 40 V DC (from distributor)
Power consumption: 0.9 VA maximum
PH201G distributor
Power supply:

100 V: 20 to130 V DC/80 to 138 V AC, 47 to 63 Hz

220 V: 120 to 340 V DC/138 to 264 V AC, 47 to 63 Hz

Power consumption: 24 V DC: approx. 200 mA
100 V AC: approx. 7 VA
220 V AC: approx. 11 VA
ISC450G inductive conductivity converter
Power supply: 90 to 264 V AC, 50/60 Hz
Power consumption: 15 VA maximum

Related Products & Solutions

2-Wire Transmitter/Analyzer FLEXA

The model FLEXA® two-wire analyzer is used for continuous on-line measurements in industrial installations. It offers an option for single or dual sensor measurement, making it the most flexible 2-wire analyzer available. The model FLEXA® modular designed series analyzer offers 4 parameter choices – pH/ORP (oxidation-reduction potential), contacting conductivity (SC), inductive conductivity (ISC) or dissolved oxygen (DO) – with the respective sensor module.

Inductive (Torodial, Electrodeless) Conductivity Analyzer

The Inductive Conductivity method is especially suitable for high conductivity measurements. The analyzer works with a sensor with two toroidal transformers built in. An AC current induces a voltage in the process sample that results in a current in the sample. The strength of this current is proportional to the conductivity of the sample following Ohm's law.

Inductive (Torodial, Electrodeless) Conductivity Sensor ISC40

The model ISC40 sensors are designed for use with the EXA ISC analyzers. This combination exceeds all expectations for conductivity measurement in terms of reliability, accuracy, rangeability and price performance. 

Conductivity Analyzers

Conductivity meters, analyzers and transmitters are used for continuous process measurement and monitoring of conductivity, resistivity, WIFI, demineralizer water, RO water, percent concentration, boiler blowdown and TDS.

Conductivity Sensors

Conductivity sensors and electrodes are used to measure process conductivity, resistivity, WIFI, demineralizer water, RO water, percent concentration, boiler blowdown and TDS. Various installation options including retractable, flow thru, immersion, and direct insertion. Proper electrode/sensor selection is critical for optimal measurement results.


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