Three-dimensional nand memory device with reduced reverse dipole effect and method for forming the same

Abstract

A memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, a memory opening vertically extending through the alternating stack, and a memory opening fill structure located in the memory opening. The memory opening fill structure includes a memory film and a vertical semiconductor channel. The memory film includes a tunneling dielectric layer, a charge storage layer that laterally surrounds the tunneling dielectric layer, a dielectric metal oxide blocking dielectric layer that laterally surrounds the charge storage layer and contacts the vertical semiconductor channel, and a silicon oxide blocking dielectric layer that laterally surrounds the dielectric metal oxide blocking dielectric layer and contacts the vertical semiconductor channel.