SEMICONDUCTOR DEVICES INCLUDING STACK OXIDE MATERIALS HAVING DIFFERENT DENSITIES OR DIFFERENT OXIDE PORTIONS, AND SEMICONDUCTOR DEVICES INCLUDING STACK DIELECTRIC MATERIALS HAVING DIFFERENT PORTIONS

摘要

Semiconductor structures may include a stack of alternating dielectric materials and control gates, charge storage structures laterally adjacent to the control gates, a charge block material between each of the charge storage structures and the laterally adjacent control gates, and a pillar extending through the stack of alternating oxide materials and control gates. Each of the dielectric materials in the stack has at least two portions of different densities and/or different rates of removal. Also disclosed are methods of fabricating such semiconductor structures.