Detection of SiO2 nanoparticles using triple‐quadrupole inductively coupled plasma‐mass spectrometry for semiconductor applications

Abstract

AbstractDetection method for SiO2 nanoparticles with the size of 20–300 nm was developed using triple‐quadrupole inductively coupled plasma‐mass spectrometer (TQ‐ICP‐MS). As 28Si+ ion of SiO2 nanoparticles is a difficult‐to‐determine ion via ICP‐MS due to severe molecular ion interferences, the mass‐to‐charge ratio of 28Si+ was shifted by reacting with O2 gas to form 28Si16O+. In order to confirm peak identification, a time‐resolved spectrum (TRS) of known standard particle was obtained, and the correlation curve of the average peak area per particle (Y) versus particle radius (X) was plotted after optimized blank subtraction. The function Y = aX3 was fitted to the data, demonstrating the validity of the developed method. As a result, the presence of 20 nm SiO2 nanoparticles, much smaller than the size (<80 nm) published in other articles, was confirmed in this work and the correlation curve can be used for on‐line monitoring of nanoparticles present in the process chemicals of the semiconductor industry.