Method of forming memory with floating gates including self-aligned metal nanodots using a polymer solution

摘要

Techniques are provided for fabricating memory with metal nanodots as charge-storing elements. In an example approach, metal salt ions are added to a core of a copolymer solution. A metal salt reduction causes the metal atoms to aggregate in the core, forming a metal nanodot. The copolymer solution is applied to a gate oxide on a substrate using spin coating or dip coating. Due to the copolymer configuration, the nanodots are held in a uniform 2D grid on the gate oxide. The polymers are selected to provide a desired nanodot size and spacing between nanodots. A polymer cure and removal process leaves the nanodots on the gate oxide. In a configuration using a control gate over a high-k dielectric floating gate which includes the nanodots, the control gates may be separated by etching while the floating gate dielectric extends uninterrupted since the nanodots are electrically isolated from one another.