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. 19, 2000
Filed:
May. 06, 1999
Chingfu Lin, Taipei, TW;
Worldwide Semiconductor Manufacturing Corp., Hsinchu, TW;
Abstract
A method of forming trench type DRAM capacitor. An insulation layer is formed on a substrate with a trench exposing a conductive region of the substrate. A first conductive layer is formed and conformal to a surface profile of the substrate. A photoresist layer is formed over the first conductive layer to fill the trench. A three-stage of etching process is carried out. A first stage of etching step is carried out to remove a portion of the photoresist layer, thereby exposing the first conductive layer. A second stage step is carried out to remove the first conductive layer by performing an isotropic dry etching step. The first conductive layer is slightly over-etched so that a portion of the first conductive layer inside the trench is also removed. Therefore, the first conductive layer inside the trench will be at a distance lower than a top surface of the insulation layer. A third stage of etching operation is carried out to remove the remaining photoresist layer so that the remaining first conductive layer inside the trench is exposed. A dielectric layer and a second conductive layer are sequentially formed over the first conductive layer.