Jong-Dae Lee

Nonvolatile Hybrid Memory Cell Embedded with Ni Nanocrystals in Poly(3-hexylthiophene)

We developed a cross-bar nonvolatile hybrid memory cell embedded with Ni nanocrystals in poly(3-hexylthiophene) (P3HT) with cell area of 4F2, where F is a feature size. The cell demonstrated nonvolatile memory characteristics, such as a memory margin (Ion/Ioff ratio) of ~5×10, over 103 endurance cycles of program-and-erase, and a retention time of 104 s at 85 °C. In addition, the mechanism of nonvolatile memory operation for the hybrid memory cell was confirmed by the combination of space-charge-limited current and a Fowler–Nordheim tunneling conduction.

Fabricated nonvolatile memory with Ag nano-crystals embedded in PVK

We have been researching the polymer nonvolatile memory-cell based on electrical bi-stability. The polymer nonvolatile memory-cell was the 4F² embedded with Ag nano-crystals in conductive polymer. The structure of polymer nonvolatile memory-cell was PVK(poly(N-vinylcarbazole) / Ag nano-crystals / PVK between the Al electrodes. The Ag nano-crystals were formed by using the curing process after evaporate several nanometers of Ag layer. The polymer nonvolatile memory-cell embedded with Ag nano-crystals showed the memory magin(ratio of I<inf>on</inf> to I<inf>off</inf>) is ∼5.0×10¹. The retention time is more than 10⁵ seconds.