Three-dimensional memory device including discrete charge storage elements and methods of forming the same

Abstract

A method of forming a memory device includes forming an alternating stack of disposable material layers and silicon nitride layers over a substrate, forming a memory opening through the alternating stack, forming a memory film and a vertical semiconductor channel in the memory opening, where the memory film includes a continuous silicon nitride charge storage material layer and a tunneling dielectric layer, forming a backside trench through the alternating stack, forming laterally-extending cavities by removing the disposable material layers selective to the silicon nitride layers through the backside trench, oxidizing portions of the silicon nitride layers and the continuous silicon nitride charge storage material layer exposed in the laterally-extending cavities to form silicon oxide insulating layers and to separate the continuous silicon nitride charge storage material layer into a vertical stack of discrete silicon nitride charge storage material portions, and replacing remaining portions of the silicon nitride layers with electrically conductive layers.