title: Low-temperature molecular vapor deposition of ultrathin metal oxide dielectric for low-voltage vertical organic field effect transistors.
abstract: We demonstrate a low-temperature layer-by-layer formation of a metal-oxide-only (AlOx) gate dielectric to attain low-voltage operation of a self-assembly based vertical organic field effect transistor (VOFET). The AlOx deposition method results in uniform films characterized by high quality dielectric properties. Pin-hole free ultrathin layers with thicknesses ranging between 1.2 and 24 nm feature bulk dielectric permittivity, εAlOx, of 8.2, high breakdownfield (>8 MV cm(-1)), low leakage currents (<10(-7) A cm(-2) at 3MV cm(-1)), and high capacitance (up to 1 μF cm(-2)). We show the benefits of the tunable surface properties of the oxide-only dielectric utilized here, in facilitating the subsequent nanostructuring steps required to realize the VOFET patterned source electrode. Optimal wetting properties enable the directional block-copolymer based self-assembly patterning, as well as the formation of robust and continuous ultrathin metallic films. Supported by computer modeling, the vertical architecture and the methods demonstrated here offer a simple, low-cost, and free of expensive lithography route for the realization of low-voltage (VGS/DS≤3 V), low-power, and potentially high-frequency large-area electronics.
authors.affiliation: Sara and Moshe Zisapel Nano-Electronic Center, Department of Electrical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.
authors.forename: Ariel J
authors.initials: AJ
authors.lastname: Ben-Sasson
authors.forename: Guy
authors.initials: G
authors.lastname: Ankonina
authors.forename: Michael
authors.initials: M
authors.lastname: Greenman
authors.forename: Michael T
authors.initials: MT
authors.lastname: Grimes
authors.forename: Nir
authors.initials: N
authors.lastname: Tessler