Patent ID: 8419959
Filing Date: 2013-04-16
Classification: H01J

Abstract:
1. A showerhead electrode for use in a plasma reaction chamber, said showerhead electrode comprising: a central portion and a peripheral portion defined by upper and lower faces of the showerhead electrode, the upper face including a planar surface extending across the central portion and the peripheral portion, the lower face defined by a planar inner surface extending across the central portion and a stepped outer surface extending across the peripheral portion, the stepped outer surface including at least one annular planar surface defining an area of increased thickness of the showerhead electrode; a plurality of circumferentially spaced apart sockets in the upper face in the peripheral portion, the sockets configured to received cam locks therein adapted to clamp the showerhead electrode to a backing plate; a plurality of gas outlets in the central portion of the showerhead electrode through which process gas can be delivered to a gap between the showerhead electrode and a lower electrode on which a wafer is supported, the gas outlets being arranged in a pattern with one center gas outlet and 13 circumferentially extending rows of gas outlets with 10 gas outlets in the first row located about 0.5 inch from the center of the showerhead electrode, 18 gas outlets in the second row located about 0.9 inches from the center, 28 gas outlets in the third row located about 1.4 inches from the center, 38 gas outlets in the fourth row located about 1.8 inches from the center, 46 gas outlets in the fifth row located about 2.3 inches from the center, 56 gas outlets in the sixth row located about 2.7 inches from the center, 66 gas outlets in the seventh row located about 3.2 inches from the center, 74 gas outlets in the eighth row located about 3.6 inches from the center, 84 gas outlets in the ninth row located about 4.1 inches from the center, 94 gas outlets in the tenth row located about 4.6 inches from the center, 104 gas outlets in the eleventh row located about 5.1 inches from the center, 110 gas outlets in the twelfth row located about 5.4 inches from the center and 120 holes in the thirteenth row located about 5.7 inches from the center; and a temperature sensor receiving hole in the upper face configured to receive a tip of a temperature sensor.