Fabrication of SiO2/SiOx/SiOxNy Non-Volatile Memory with Transparent Amorphous Indium Gallium Zinc Oxide Channels

In this paper, we investigated the electrical and memory properties of nonvolatile memory (NVM) using low temperature multi-stack gate insulators of SiO 2 /SiO x /SiO x N y (OOxOn) and an active layer using amorphous InGaZnO (a-IGZO) films. The various amorphous SiO x materials were studied by controlling the gas flow ratio of SiH 4 :N 2 O from 2:1 to 1:2 to determine the optimal conditions for the charge-trapping layer. The NVM devices using the OOxOn structure were investigated with SiO x N y tunneling thicknesses changing between 2.2, 2.5, and 2.8 nm. The characteristics of the NVM device with 2.8 nm SiO x N y tunneling thickness showed a retention exceeding 97% of threshold voltage shift after 10 4 s and greater than 93% after 10 years with low +13 V at an only programming duration of 1 ms. In addition, the optical transmittance of the a-IGZO films was measured the be over 85%. It is a promising candidate for achieving flexible displays and transparency on plastic substrates because of the possibility of the low-temperature deposition and high transparent properties of a-IGZO films. Therefore, the bottom-gate OOxOn NVM using high transparent a-IGZO active layer has become a potential device for flexible memory displays system.