Patent ID: 7799134

Claim:
A shower plate for a plasma CVD apparatus comprising a first electrode with a shower plate having a first face that faces a second electrode, wherein the first face of the shower plate includes: an exterior base surface facing the second electrode and having multiple apertures for passing a gas therethrough, each aperture extending from the exterior base surface to a face other than the exterior base surface; and multiple discontinuous protrusions each having the same size and separately protruding in a direction toward the second electrode and extending from the exterior base surface along the thickness direction of the shower plate and being dispersed among the apertures, wherein a tip of each protrusion faces the second electrode away from the exterior base surface having the apertures, a distance between any one of the protrusions and any one of the apertures adjacent to each other is smaller than a distance between the protrusion and any protrusion adjacent to the protrusion, the number of the apertures is greater than the number of the protrusions.