title: Floating gate memory with charge storage dots array formed by Dps protein modified with site-specific binding peptides.
abstract: We report a nanodot (ND) floating gate memory (NFGM) with a high-density ND array formed by a biological nano process. We utilized two kinds of cage-shaped proteins displaying SiO2 binding peptide (minTBP-1) on their outer surfaces: ferritin and Dps, which accommodate cobalt oxide NDs in their cavities. The diameters of the cobalt NDs were regulated by the cavity sizes of the proteins. Because minTBP-1 is strongly adsorbed on the SiO2 surface, high-density cobalt oxide ND arrays were obtained by a simple spin coating process. The densities of cobalt oxide ND arrays based on ferritin and Dps were 6.8 × 10(11) dots cm(-2) and 1.2 × 10(12) dots cm(-2), respectively. After selective protein elimination and embedding in a metal-oxide-semiconductor (MOS) capacitor, the charge capacities of both ND arrays were evaluated by measuring their C-V characteristics. The MOS capacitor embedded with the Dps ND array showed a wider memory window than the device embedded with the ferritin ND array. Finally, we fabricated an NFGM with a high-density ND array based on Dps, and confirmed its competent writing/erasing characteristics and long retention time.
authors.affiliation: Nara Institute of Science and Technology, 8916-5, Takayama, Ikoma, Nara 630-0192, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kamitake
authors.forename: Mutsunori
authors.initials: M
authors.lastname: Uenuma
authors.forename: Naofumi
authors.initials: N
authors.lastname: Okamoto
authors.forename: Masahiro
authors.initials: M
authors.lastname: Horita
authors.forename: Yasuaki
authors.initials: Y
authors.lastname: Ishikawa
authors.forename: Ichro
authors.initials: I
authors.lastname: Yamashita
authors.forename: Yukiharu
authors.initials: Y
authors.lastname: Uraoka
mesh_terms: D000818:Animals; D003035:Cobalt / Q000737:chemistry; D006736:Horses; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010087:Oxides / Q000737:chemistry; D010316:Particle Size; D010455:Peptides / Q000737:chemistry*; D056951:Photoelectron Spectroscopy; D011506:Proteins / Q000737:chemistry*; D012666:Semiconductors; D014961:X-Ray Diffraction
chemical_list: D010087:Oxides; D010455:Peptides; D011506:Proteins; D003035:Cobalt; C060728:cobalt oxide