Related Experiment Video
Updated: Aug 7, 2026
07:37
Revealing Dynamic Processes of Materials in Liquids Using Liquid Cell Transmission Electron Microscopy
Published on: December 20, 2012
Dropping mode chemiluminescence system with a poly(dimethylsiloxane) cell for applications to semiconductor processes
1Department of Chemistry, Dankook University, Hannam-dong, Seoul, Korea.
Summary
A novel chemiluminescence system using a disposable polymer cell accurately detects ultra-trace metal ions in semiconductor manufacturing fluids like hydrofluoric acid. This method offers a sensitive, reproducible, and cost-effective on-line monitoring solution for critical metal contaminants.
Area of Science:
- Analytical Chemistry
- Materials Science
- Chemical Engineering
Background:
- Semiconductor manufacturing relies on ultra-pure chemicals, making metal ion contamination detection critical.
- Traditional methods for detecting trace metals in harsh chemicals like hydrofluoric acid (HF) can be challenging due to reagent instability and sample matrix effects.
- Developing robust and sensitive sensors for on-line monitoring of metal ions in process chemicals is essential for quality control.
Purpose of the Study:
- To develop and validate a cost-effective chemiluminescence (CL) system for ultra-trace metal ion determination.
- To utilize a novel polymer cell made of poly(dimethylsiloxane) (PDMS) for enhanced chemical resistance, particularly to hydrofluoric acid (HF).
- To establish a reliable method for on-line monitoring of metal contaminants in semiconductor manufacturing solutions.
Main Methods:
- A chemiluminescence system employing a dropping mode for sample injection was designed.
- A disposable poly(dimethylsiloxane) (PDMS) polymer cell was fabricated for its inertness to HF and optical transparency.
- Ultra-trace metal ions, specifically Fe2+, were quantified in various semiconductor process solutions, including HF and SC-1, using a luminol-H2O2 reagent.
- The system utilized a small sample volume (7.17 microg) to minimize reagent disturbance and prevent precipitation.
Main Results:
- The PDMS polymer cell demonstrated excellent chemical inertness, especially towards hydrofluoric acid (HF).
- The dropping method ensured high reproducibility (±0.37% RSD) and minimized pH fluctuations.
- Ultra-trace levels of Fe2+ were detected with limits of detection between 42 and 62 pg mL−1 in different solutions.
- The system proved sensitive, reproducible, and resistant to HF, suitable for on-line monitoring.
Conclusions:
- The developed chemiluminescence system with a PDMS cell is a viable tool for on-line monitoring of metal contamination in semiconductor manufacturing.
- The system offers advantages such as low sample consumption, reduced waste generation, and robustness in harsh chemical environments.
- While lacking selectivity for individual metal ions, it effectively monitors overall metal contamination levels of concern (e.g., Fe, Cu, Co).
