Detection of Precursor Molecules in the MCR-CVD (metal chloride reduction-chemical vapor deposition) of Copper

Gaseous metal chlorides can be precursors in a novel CVD method called metal chloride reduction-chemical vapor deposition (MCR-CVD). In the present study, we focused on the etching process of MCR-CVD of copper. There are more than one species in the gas phase of copper chlorides, which are considered to work as precursors. We detected gaseous copper chloride molecules generated by etching of copper surface by mass spectrometry. The composition of gaseous species might change by gas phase reactions. The etching process of copper surface by chlorine could not be regarded as equilibrium process.