Nonvolatile Memory Characteristics Induced in High-k Dielectric Thin Films through Electron Irradiation

Abstract

The current research aims to develop a simplified fabrication procedure for a nano-floating gate memory by using electron beam irradiation. The main strategy is to combine nanoscale high-k dielectric thin films with highly accelerated electron beams, unlike the conventional approach involving multicomponent nanolaminates with dissimilar materials. This work investigated Al2O3 as a high-k dielectric thin film for testing the electron irradiation on high-k thin film materials. The Al2O3 thin films exhibited highly superior memory characteristics compared to those of the preexisting nano-floating gate memories into which charge-trapped components were incorporated for robust high-k dielectrics. The optimized Al2O3 thin films exhibited long-lasting retention features; approximately 75% of the programming information was maintained compared to that of the initial setting value, and the erasing information did not change over time. Furthermore, the irradiated Al2O3 thin films exhibited the highest trap density of 7 x 10(12) traps/cm(2).