Method of forming multi-level coplanar metal/insulator films using dual damascene with sacrificial flowable oxide

US6300235A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Klaus Feldner · Dresden, DE
• Virinder Grewal · Wappingers Falls, US
• Bernd Vollmer · Beacon, US
• Rainer Florian Schnabel · Weilmünster, DE

Key dates

• Filing date: Jun 30, 1997
• Grant date: Oct 9, 2001
• Expiry date: Jun 30, 2017

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/76808
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

An improved method of performing a dual damascene etch through a layer stack disposed above a substrate. The layer stack includes an underlying device layer and an insulating layer disposed above the underlying device layer. The method includes forming a trench in a top surface of the insulating layer such that the trench is positioned over the underlying device layer and separated therefrom by insulating material at a bottom of the trench. The method also includes, depositing flowable oxide over the top surface of the insulating layer and into the trench followed by planarizing the flowable oxide down to about a level of the top surface of the insulating layer. Further, the method includes, etching through the flowable oxide within the trench and through insulating material at the bottom of the trench down to the underlying device layer to form a via.