Patent ID: 8876024
Filing Date: 2014-11-04
Classification: B32B,C23C,H01J,Y10T

Abstract:
1. A showerhead assembly, comprising: a backing plate; a first gas distribution plate comprising aluminum and coupled to the backing plate to define a first plenum therebetween and having a first side coupled to the backing plate, a second side having an annular groove bored therein, and two or more zones, each zone having a plurality of first bores extending through the first gas distribution plate from the first plenum to a plurality of first expanding channels that extend to the annular groove; and a second gas distribution plate comprising silicon carbide and coupled to the first gas distribution plate to define a second plenum between the annular groove and the second gas distribution plate, the second gas distribution plate having a third side, a fourth side, and a plurality of second bores extending from the second plenum to the fourth side through the second gas distribution plate, the third side of the second gas distribution plate coupled with the second side of the first gas distribution plate, and the number of second bores exceeds the number of first bores.