Low-temperature polycrystalline silicon thin film transistor nonvolatile memory using Ni nanocrystals as charge-trapping centers fabricated by hydrogen plasma process

Processes for fabricating a Ni nanocrystal (NC)-assisted low-temperature polycrystalline silicon thin film transistor (LTPS-TFT) nonvolatile memory device of noble stack below 600 °C were successfully developed. The NCs were fabricated in H-plasma atmosphere by heating a nanosized Ni film to realize an appropriate nanoparticle distribution. Results show that NCs with a number density of ∼5 × 10¹¹ cm^-2 and a particle diameter of 4 to 12 nm can successfully be fabricated as charge-trapping centers for enhancing the device performance. The results also indicate that the data retentions at the initial time and after 10⁴ s for a SiO ₂/Ni-NCs/Si₃N₄/SiO₂ gate under the present stack of devices are about 2.2 and ∼1.1 V, respectively.