Taiwan Semiconductor Manufacturing Comp. Ltd.

Feng-Yueh Chang

Jyh-Shiou Hsu

Pin-Yi Hsin

Chuan-Chieh Huang

Chi-Lien Lin

A method of forming a narrow diameter opening in an insulator layer, featuring a vertical shape profile, has been developed. Using a photoresist shape as an etch mask a first plasma procedure is used to form an initial opening, with a tapered profile shape, in the insulator layer exposing a portion of the top surface of an underlying stop layer. The first plasma procedure results in formation of a thin polymer layer located at the bottom of the initial opening. A second plasma procedure performed in situ, results in deposition of additional polymer layer, comprised of carbon and fluorine, at the bottom of the initial opening. This is followed by a third plasma procedure, performed in situ in an oxygen plasma, removing polymer and releasing fluorine based radicals which etch portions of insulator layer exposed at the bottom of the initial opening, resulting in a final opening featuring a vertical profile shape.

Method to improve via or contact hole profile using an in-situ polymer deposition and strip procedure

A method for plasma etching a semiconductor feature to improve an etching profile including providing a semiconductor wafer comprising a first feature opening anisotropically etched though a thickness portion of at least one dielectric insulating layer; anisotropically etching a second feature opening overlying and at least partially encompassing the first feature opening according to a reactive ion etch (RIE) process to leave an unetched portion surrounding a first feature opening portion at about a bottom portion level of the second feature opening; and, plasma treating the first and second openings with a plasma formed of a mixture of oxygen and nitrogen plasma source gases including an applying an independently variable RF bias power source to the semiconductor wafer to remove the unetched portion.

Growing community of inventors

Banchiau, Taiwan

Feng-Yueh Chang