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:
Nov. 10, 1998
Filed:
Apr. 22, 1996
Taiwan Semiconductor Manufacturing Company, Ltd., Hsin-Chu, TW;
Abstract
A method is described for overcoming the non-conformity and poor step coverage incurred when materials such as metals and barrier layers are deposited into contact openings by physical-vapor-deposition(PVD) techniques such as sputtering and evaporation. Conventional PVD deposition into a vertical walled opening results in a deposit whose thickness diminishes towards the base of the opening. This causes voids when the opening is subsequently filled by chemical-vapor-deposited(CVD) tungsten as well as potential failure of the barrier material due to inadequate coverage at the base of the opening. The method utilizes a two stage reactive ion etching technique to selectively etch the upper portion of the deposited layer while protecting the lower portion with photoresist. A second deposition of barrier layer material then restores material at the top of the opening while augmenting the thickness at the base. This reduces the negative taper of the opening and allows total filling by the subsequent CVD deposition.