US 2009/0000742 A1 · Shower Plate and Method for Manufacturing the Same

Abstract

Disclosed is a shower plate which is formed with a large number of process-gas blowing holes having a simple structure, high machinability and high dimensional accuracy without the risk of unevenness in blowing of a process gas and outbreak of particles, while ensuring constant quality and interchangeability. Through a press forming process, a powder for a ceramic material with a low dielectric constant is formed into a disc-shaped compact having dimensions determined in consideration of a sintering shrinkage value and a machining value. A gas inlet passage 3 and a large number of blowing holes 2 for a compact stage are bored in the disc-shaped compact, and then the disc-shaped compact is sintered. Subsequently, the gas inlet passage 3 and a main hole portion 2b in each of the blowing holes are subjected to grinding to have a surface roughness of Is or less. Further, a lapping wire having a taper-shaped end is inserted into an outlet port 2a of the blowing hole 2, and reciprocatingly moved while being slidingly displaced in such a manner that a portion of the lapping wire located in the outlet port 2a is gradually increased in wire diameter, so that the outlet port 2a is lapped to have a diameter of from 0.1 mm to less than 0.3 mm, a dimensional accuracy within ±0.002 mm, and a surface roughness of 1 s or less.

Claims12

Dependent claims

A shower plate comprising:

a disc-shaped plate body;
a gas inlet passage including an elongated hole and an opening in communication with said elongated hole, said elongated hole being extended linearly from a side face of said plate body toward a center portion thereof, said opening being bored in said disc-shaped plate body to extend from an end of said elongated hole to a back surface of said disc-shaped plate body in a direction perpendicular to said elongated hole;
and
a number of blowing holes for blowing out a process gas therefrom, each of said blowing holes being bored in said disc-shaped plate body from said back surface to a front surface of said disc-shaped plate body,
wherein each of said blowing holes includes a main hole portion and an outlet port which are arranged in communication on the same axis, said outlet port having a diametral dimension of from 0.1 mm to less than 0.3 mm with a dimensional tolerance of the diameter of said outlet port being within ±0.002 mm.

2 more elements

A method of manufacturing a shower plate, comprising the steps of:

inserting a lapping wire having a taper-shaped end portion, into one of a number of blowing holes of the shower plate comprised of a sinterable ceramic material;
and
reciprocatingly moving said lapping wire or said shower plate while slidingly displacing said lapping wire in such a manner that a portion of said lapping wire located in an outlet port of said blowing hole is changed from said end portion toward a base portion of said lapping wire, so as to lap said outlet port of said blowing hole.

Dependencies are inferred from the claim text.

Shower Plate and Method for Manufacturing the Same

Life of this patent

Shower Plate and Method for Manufacturing the Same

Life of this patent

Abstract

Claims12