Hin Yiu Anthony Chung

Very sensitive real-time inline process mass spectrometer based on FFT Ion Trap technique

In this work, we introduce a new, very fast and extremely sensitive inline process mass spectrometry technique based on Fourier-Transform 3D-Quadrupole Ion Trap technology. With this new technology, we have successfully detected sub-ppbV AsH3 and single digit pptV B2H6 dopants in H2 process gases within seconds. Real-time inline measurement at a CVD chamber showed that our technology was capable to detect reaction products, contaminations on the wafer holder and dopant memory effects in real-time. In contrast to typical residual gas analyzers, our new 3D-Quadrupole Ion Trap did not show mass discrimination with increasing m/z-ratio and was therefore capable to detect large molecules with very low concentrations.