Hot carrier injection programmable structure including discontinuous storage elements and spacer control gates in a trench and a method of using the same

摘要

A programmable storage device includes a first diffusion region underlying a portion of a first trench defined in a semiconductor substrate and a second diffusion region occupying an upper portion of the substrate adjacent to the first trench. The device includes a charge storage stack lining sidewalls and a portion of a floor of the first trench. The charge storage stack includes a layer of discontinuous storage elements (DSEs). Electrically conductive spacers formed on opposing sidewalls of the first trench adjacent to respective charge storage stacks serve as control gates for the device. The DSEs may be silicon, polysilicon, metal, silicon nitride, or metal nitride nanocrystals or nanoclusters. The storage stack includes a top dielectric of CVD silicon oxide overlying the nanocrystals overlying a bottom dielectric of thermally formed silicon dioxide. The device includes first and second injection regions in the layer of DSEs proximal to the first and second diffusion regions.