Patent ID: 8933501
Filing Date: 2015-01-13
Classification: H01L

Abstract:
1. A monolithic three dimensional NAND string, comprising: a semiconductor channel, at least one end portion of the semiconductor channel extending substantially perpendicular to a major surface of a substrate; a plurality of control gate electrodes having a strip shape with major surfaces extending substantially parallel to the major surface of the substrate, wherein the plurality of control gate electrodes comprise at least a first control gate electrode located in a first device level and a second control gate electrode located in a second device level located over the major surface of the substrate and below the first device level, wherein the first control gate electrode is separated from the second control gate electrode by an air gap located substantially between the major surfaces of the first and second control gate electrodes; a blocking dielectric layer located in contact with the plurality of control gate electrodes; a plurality of spaced apart charge storage segments, wherein the plurality of spaced apart charge storage segments comprise at least a first spaced apart charge storage segment located in the first device level and a second spaced apart charge storage segment located in the second device level; and a tunnel dielectric layer located between each one of the plurality of the spaced apart charge storage segments and the semiconductor channel.