Method of operating high density plasma cvd reactor with combined inductive and capacitive coupling

Abstract

The invention is embodied in a method of cleaning a plasma reactor by creating a vacuum in the chamber while introducing an etchant gas into the chamber through the gas injection ports, and applying RF energy to a ceiling electrode in the chamber while not necessarily applying RF energy to the coil antenna, so as to strike a predominantly capacitively coupled plasma in the vacuum chamber. In another embodiment the method includes, whenever the reactor is to be operated in an inductive coupling mode, applying RF power to the reactors coil antenna while grounding the ceiling electrode, and whenever the reactor is to be operated in a capacitive coupling mode, applying RF power to the ceiling electrode, and whenever the reactor is to be cleaned, cleaning the reactor by applying RF power to the ceiling electrode and to the coil antenna while introducing an etchant gas into the vacuum chamber. In yet another embodiment the method includes performing chemical vapor deposition on a wafer by introducing a deposition precursor gas into the chamber while maintaining an inductively coupled plasma therein by applying RF power to the coil antenna while grounding the ceiling electrode, and cleaning the reactor by introducing a precursor cleaning gas into the chamber while maintaining a capacitively coupled plasma in the chamber by applying RF power to the ceiling electrode.