The removal of silicon oxychloride films deposited on the chamber walls during Cl2/O2 plasma etching of Si using an SF6 plasma was studied using multiple surface and plasma diagnostic techniques. Focus was on the changes in the gas phase and in the chemical composition of the silicon oxychloride film as it is removed by F atoms in an SF6 plasma. Films depositing and species adsorbing on the chamber walls during the deposition and cleaning steps were detected by a real time, in situ diagnostic probe. The radicals in the discharge were detected by optical emission spectroscopy (OES) while stable gas species present in the exhaust of the reactor were detected through gas phase FTIR absorption spectroscopy. Simultaneous monitoring of the walls and the gas phase yielded insights into the cleaning mechanism of the silicon oxychloride deposits by SF6 plasma.
|Original language||English (US)|
|Number of pages||7|
|Journal||Journal of Vacuum Science and Technology A: Vacuum, Surfaces and Films|
|State||Published - Jul 2002|