The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 24, 2013
Filed:
Dec. 07, 2011
Hsiao-chia Chen, Taichung, TW;
Sheng-chang Liang, Taichung, TW;
Chien-hua Tsai, Taichung, TW;
Masahiko Ohuchi, Taichung, TW;
Hsiao-chia Chen, Taichung, TW;
Sheng-chang Liang, Taichung, TW;
Chien-hua Tsai, Taichung, TW;
Masahiko Ohuchi, Taichung, TW;
Rexchip Electronics Corporation, Taichung, TW;
Abstract
A method of manufacturing vertical transistors includes steps of: forming a conductive layer on the surface of a substrate with a ditch and two support portions; removing the conductive layer on the bottom wall of the ditch and top walls of the support portions via anisotropic etching through a etch back process; forming an oxidized portion in the ditch; and etching the conductive layer to form two gates without contacting each other. By forming the conductive layer on the surface of the ditch and adopting selective etching of the etch back process, the problem of forming sub-trenches caused by lateral etching or uneven etching rate that might otherwise occur in the conventional etching process is prevented, and the risk of damaging metal wires caused by increasing etching duration also can be averted.