ALEXANDRIA, Va., Oct. 28 -- United States Patent no. 12,451,385, issued on Oct. 21, was assigned to NGK INSULATORS Ltd. (Nagoya, Japan).
"Wafer placement table" was invented by Masaki Ishikawa (Handa, Japan), Tatsuya Kuno (Nagoya, Japan) and Yusuke Ogiso (Nagakute, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A wafer placement table includes: a ceramic plate having a wafer placement surface on an upper surface and a built-in electrode; a plug placement hole extending through the ceramic plate from a lower surface to the upper surface; a plug placed in the plug placement hole and allowing gas to pass therethrough; and a plug joint joining an outer edge of an upper surface of the plug and an upper open...