×

Self-aligned three-dimensional non-volatile memory fabrication

  • US 8,105,867 B2
  • Filed: 05/19/2009
  • Issued: 01/31/2012
  • Est. Priority Date: 11/18/2008
  • Status: Expired due to Fees
First Claim
Patent Images

1. A method of fabricating non-volatile storage, comprising:

  • forming over a substrate a first conductor elongated in a first direction, the first conductor having sidewalls elongated in the first direction;

    forming a second conductor elongated in a second direction that is substantially perpendicular to the first direction, the second conductor being vertically-separated from the first conductor and having sidewalls elongated in the second direction, wherein forming the second conductor includes etching a first layer of conductive material into a first strip of conductive material using a first pattern and etching a second layer of conductive material into a second strip of conductive material using a second pattern, the first strip of conductive material forming a first portion of the sidewalls of the second conductor and the second strip of conductive material forming a second portion of the sidewalls of the second conductor;

    forming a third conductor elongated in the first direction, the third conductor being vertically-separated from the first conductor and the second conductor and having sidewalls elongated in the first direction;

    etching a first layer stack using the first pattern to form a first pillar between the first conductor and the second conductor, the first pillar having first sidewalls elongated in the first direction and second sidewalls elongated in the second direction, the first sidewalls of the first pillar being self-aligned with the sidewalls of the first conductor and the second sidewalls of the first pillar being self-aligned with at least the first portion of the sidewalls of the second conductor, the first pillar including a steering element and at least one state change element, wherein etching the first layer of conductive material and the first layer stack using the first pattern defines the second sidewalls of the first pillar and the first portion of the sidewalls of the second conductor; and

    etching a second layer stack using the second pattern to form a second pillar between the second conductor and the third conductor, the second pillar having first sidewalls elongated in the first direction and second sidewalls elongated in the second direction, the first sidewalls of the second pillar being self-aligned with the sidewalls of the third conductor and the second sidewalls of the second pillar being self-aligned with at least the second portion of the sidewalls of the second conductor, the second pillar including a steering element and at least one state change element, the second portion of the sidewalls of the second conductor being misaligned with the first portion of the sidewalls of the second conductor, wherein etching the second layer of conductive material and the second layer stack using the second pattern defines the second sidewalls of the second pillar and the second portion of the sidewalls of the second conductor.

View all claims
  • 4 Assignments
Timeline View
Assignment View
    ×
    ×