Self-aligned non-volatile memory cell

US7504686B2 · kind B2 · utility

Assignee

• Sandisk, Inc. · US

Inventors

• Jeffrey W. Lutze · San Jose, US
• Tuan Pham · Santa Clara, US
• Henry Chien · San Jose, US
• George Matamis · Danville, US

Key dates

• Filing date: Sep 1, 2006
• Grant date: Mar 17, 2009
• Expiry date: Sep 1, 2026

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/035

Abstract

Floating gate structures are disclosed that have a projection that extends away from the surface of a substrate. This projection may provide the floating gate with increased surface area for coupling the floating gate and the control gate. In one embodiment, the word line extends downwards on each side of the floating gate to shield adjacent floating gates in the same string. In another embodiment, a process for fabricating floating gates with projections is disclosed. The projection may be formed so that it is self-aligned to the rest of the floating gate.