Showerhead electrode
AssigneeLam Research Corporation
InventorsAnthony de la Llera, Pratik Mankidy, Michael C. Kellogg, Rajinder Dhindsa
Life of this patent
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Abstract
A showerhead electrode, a gasket set and an assembly thereof in plasma reaction chamber for etching semiconductor substrates are provided with improved a gas injection hole pattern, positioning accuracy and reduced warping, which leads to enhanced uniformity of plasma processing rate. A method of assembling the inner electrode and gasket set to a supporting member includes simultaneous engagement of cam locks.
Claims17
A showerhead electrode for a showerhead electrode assembly in a parallel plate capacitively coupled plasma processing chamber, the showerhead electrode assembly comprising a backing plate having gas injection holes extending between upper and lower faces thereof, a plurality of stud/socket assemblies and cam shafts, an alignment ring, and a plurality of alignment pins;
- the showerhead electrode comprising:
- a plasma exposed surface on a lower face thereof;
- a mounting surface on an upper face thereof;
- a plurality of gas injection holes extending between the plasma exposed surface and the mounting surface thereof and arranged in a pattern matching the gas injection holes in the backing plate;
- wherein the gas injection holes have a diameter less than or equal to 0.04 inch and are arranged in a pattern with one center gas injection hole at a center of the electrode and eight concentric rows of gas injection holes, the first row having seven gas injection holes located at a radial distance of about 0.6-0.7 inch from the center of the electrode;
- the second row having seventeen gas injection holes located at a radial distance of about 1.3-1.4 inches from the center of the electrode;
- the third row having twenty-eight gas injection holes located at a radial distance of about 2.1-2.2 inches from the center of the electrode;
- the fourth row having forty gas injection holes located at a radial distance of about 2.8-3.0 inches from the center of the electrode;
- the fifth row having forty-eight gas injection holes located at a radial distance of about 3.6-3.7 inches from the center of the electrode;
- the sixth row having fifty-six gas injection holes located at a radial distance of about 4.4-4.5 inches from the center of the electrode;
- the seventh row having sixty-four gas injection holes located at a radial distance of about 5.0-5.1 inches from the center of the electrode;
- the eighth row having seventy-two gas injection holes located at a radial distance of about 5.7-5.8 inches from the center of the electrode;
- the gas injection holes in each row are azimuthally equally spaced.
Dependencies are inferred from the claim text.