US Patent No. 10,920,318

SHOWER PLATE, SEMICONDUCTOR MANUFACTURING APPARATUS, AND METHOD FOR MANUFACTURING SHOWER PLATE


Patent No. 10,920,318
Issue Date February 16, 2021
Title Shower Plate, Semiconductor Manufacturing Apparatus, And Method For Manufacturing Shower Plate
Inventorship Yukio Noguchi, Kyoto (JP)
Yuuji Kawase, Kyoto (JP)
Hiromasa Matsufuji, Kyoto (JP)
Kouji Teramoto, Kyoto (JP)
Assignee KYOCERA Corporation, Kyoto (JP)

Claim of US Patent No. 10,920,318

1. A shower plate, comprising:a ceramic sintered body comprising:
a first surface;
a second surface facing the first surface; and
a through hole positioned between the first surface and the second surface,
wherein
an inner surface of the through hole comprising a protruding crystal grain which protrudes more than an exposed part of a grain boundary phase existing between crystal grains, and
the inner surface of the through hole comprises an arithmetic average roughness in an axial direction of the through hole in a range from 0.3 ?m to 0.6 ?m.