Design of an E²PROM memory cell less than 100 square microns using 1 micron technology

Synthesis and characterization of aerosol silicon nanocrystal nonvolatile floating-gate memory devices

“…The memory operation of the aerosol nanocrystal floating-gate MOSFET depends on charge storage in the floating-gate, similar to conventional stacked-gate nonvolatile memory devices. 1 In a silicon nanocrystal nonvolatile memory device, however, charge is not stored on a continuous floating-gate polysilicon layer as is the case in conventional stacked-gate devices, but on a discontinuous floating-gate layer composed of discrete crystalline silicon nanocrystals. [2][3][4] Nanocrystal charge storage offers several potential advantages over conventional stacked-gate nonvolatile memory devices; ͑1͒ a simple low cost floating-gate fabrication process; ͑2͒ improved retention resulting from Coulomb blockade and quantum confinement effects 5 that enable the use of thinner tunnel oxides and lower operating voltages; ͑3͒ reduced punchthrough achieved by eliminating drain-to-floating-gate coupling, allowing higher drain voltages during readout, shorter channel lengths, and smaller cell area; and ͑4͒ excellent immunity to stress induced leakage current and defects within the floating-gate or insulating layers due to the distributed nature of the charge storage in the discontinuous nanocrystal layer.…”