Nonvolatile flash memory based on biologically integrated nanostructures

(Nanowerk News) Researchers demonstrate a novel process to fabricate hierarchical nanoarchitectures of multilayered nanodots and apply these nanostructures in memory devices (published online in Langmuir: "Nonvolatile Flash Memory Based on Biologically Integrated Hierarchical Nanostructures").
The team of Japanese researchers fabricated memory nodes made up of biochemically synthesized ferrihydrite bionanodots (Fe-BND) in protein cavities by biomimetic layer-by-layer assembly (BioLBL) using the specific binding and mineralization function of peptide aptamer minTBP-1 attached to the exterior of nanoparticle-accommodated recombinant minT1-LF.
MinT1-LF successfully aligned to form separate layers using the wet chemical process of BioLBL. The fabricated Fe-BND array was embedded into a stacked metal oxide-semiconductor (MOS) device structure as a charge storage node.
3D nanoparticle architecture with multilayered structur
Three-dimensional (3D) nanoparticle architecture with multilayered structure was fabricated by the biological layer-by-layer method and embedded in a metal oxide–semiconductor device structure as a charge storage node of a flash memory device. The 3D-integrated multilayered nanoparticle architecture successfully worked as a charge storage node in flash memory devices that exhibited improved charge storage capacity compared with that of a conventional monolayer structure device. (© ACS) (click image to enlarge)
The MOS capacitor showed memory operation, and an increase of bionanodot layer number increased the charge storage ability of the memory device.
The authors note that, in this study, they only examined Fe@minT1-LF in MOS capacitors; however, ferritin can incorporate various kinds of nanoparticles in its cavity, not only by biomineralization but also by nanoparticle-directed assembly. "By using different nanoparticles encapsulated in minT1-LF, we can fabricate heterogeneous layers of different nanoparticles with divergent electronic properties such as band gap."
This approach can be used to develop novel types of multilayered memory devices. Moreover, applications of heterogeneous nanoparticle multilayers made by the BioLB method are not restricted to memory devices but can be applied to optoelectronics, battery cells, and so on.
Source: American Chemical Society