Method of forming recessed container cells

US5888877A · kind A · utility

Assignee

• Micron Technology, Inc. · US

Inventors

• Charles H. Dennison · San Jose, US
• Bradley J. Howard · Boise, US
• Mark E. Jost · Boise, US

Key dates

• Filing date: Oct 28, 1997
• Grant date: Mar 30, 1999
• Expiry date: Oct 28, 2017

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D1/047

Abstract

A container capacitor having a recessed conductive layer. The recessed conductive layer is typically made of polysilicon. The recessed structure reduces the chances of polysilicon "floaters," which are traces of polysilicon that remain on the surface of the substrate, coupling adjacent capacitors together to create short circuits. The disclosed method of creating such a recessed structure uses chemical mechanical planarization to remove the layer of polysilicon and an overlying layer of photoresist from the upper surface of the substrate in which a container is formed. A dry etch selectively isolates a rim of the polysilicon within the container to recess the rim, while the remainder of the polysilicon in the container is protected by the layer of photoresist.