Patent ID: 8946048
Filing Date: 2015-02-03
Classification: H01L

Abstract:
1. A method of fabricating non-volatile storage using a substrate, comprising: forming a first layer stack column and a second layer stack column, each layer stack column including a tunnel dielectric strip, a charge storage strip and an intermediate dielectric strip, the first layer stack column overlying a first active area of the substrate and the second layer stack column overlying a second active of the substrate; forming an isolation region in the substrate between the first active area and the second active area after forming the first layer stack column and the second layer stack column; at least partially filling the isolation region with a sacrificial material; forming a dielectric strip over the isolation region, the dielectric strip extending between the intermediate dielectric strip in the first layer stack column and the intermediate dielectric strip in the second layer stack column, the dielectric strip having a lower dielectric constant than a dielectric constant of the intermediate dielectric strips; forming a control gate layer after forming the dielectric strip over the isolation region; etching the control gate layer, the first layer stack column, and the second layer stack column to form a plurality of layer stack rows including a first layer stack row and a second layer stack row; and removing at least a portion of the sacrificial material to form a bit line air gap in the isolation region after etching the first layer stack column and the second layer stack column.