High density plasma CVD reactor with combined inductive and capacitive coupling

Abstract

The invention is embodied in a plasma reactor having a vacuum chamber with a cylindrical side portion and a ceiling at a certain height above the top of the cylindrical side portion, a wafer-holding pedestal near the bottom of the vacuum chamber, gas injection ports near the cylindrical side portion and a vacuum pump, the reactor including a generally planar disk-shaped conductive ceiling electrode adjacent the ceiling, a helical coil antenna having a bottom winding near the top of the cylindrical side portion and a top winding generally corresponding to the second diameter near the planar disk-shaped conductive ceiling electrode, the helical coil antenna substantially spanning the height between the top of the cylindrical side portion and the ceiling, and a switch for individually connecting each one of the coil antenna, the ceiling electrode and the wafer pedestal to one of (a) a respective RF power source or (b) ground or (c) a floating potential (i.e., unconnected to any potential source). The invention is also embodied in a plasma reactor having a vacuum chamber, a wafer-holding pedestal near the bottom of the vacuum chamber, gas injection ports and a vacuum pump, the reactor including a conductive ceiling electrode at the top of the chamber, a coil antenna having a top generally coplanar with the ceiling electrode and a base generally coinciding with a circumference of the vacuum chamber, and a switch for individually connecting each one of the coil antenna, the ceiling electrode and the wafer pedestal to one of (a) a respective RF power source, or (b) ground or (c) a floating potential. In one embodiment, the reactor is a chemical vapor deposition plasma reactor.

Dependencies are inferred from the claim text.