Metal contact via structure surrounded by an air gap and method of making thereof

US10319680B1 · kind B1 · utility

Assignee

• Sandisk Technologies, Inc. · US

Inventors

• Jongsun Sel · Los Gatos, US
• Masaaki Higashitani · Cupertino, US
• Mohan Dunga · Santa Clara, US
• Fumiaki Toyama · Cupertino, US
• Peter Rabkin · Cupertino, US

Key dates

• Filing date: Mar 1, 2018
• Grant date: Jun 11, 2019
• Expiry date: Mar 1, 2038

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L2221/1063
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A structure includes a metal interconnect structure embedded in a lower interconnect level dielectric layer overlying a substrate, at least one material layer overlying the metal interconnect structure, a first contact level dielectric layer overlying the at least one material layer; a metal contact via structure vertically extending through the first contact level dielectric layer and the at least one material layer and contacting a top surface of the metal interconnect structure, and an encapsulated tubular cavity laterally surrounding at least a lower portion of the metal contact via structure, and vertically extending through the at least one material layer.