Donna M. Joyce

Deoxyribonucleic acid-ceramic hybrid dielectrics for potential application as gate insulators in organic field effect transistors

Hybrid films incorporating high dielectric constant k ceramics (BaTiO3 and TiO2) in deoxyribonucleic acid (DNA) were fabricated from highly stable dispersions of the ceramic nanoparticles in viscous, aqueous DNA solutions. Dielectric and electrical properties of the as-prepared nanocomposite films were investigated for potential use as gate insulators in organic field effect transistors. A k value as high as 14 was achieved with a 40 wt. % loading of ceramic nanoparticles in DNA. Electrical resistivities on the order of 1014 Ω cm with leakage current densities on the order of 10−9 A/cm2 were measured from current-voltage experiments under electric field biases up to 50 V/μm.

Deoxyribonucleic acid-based hybrid thin films for potential application as high energy density capacitors

Deoxyribonucleic acid (DNA) based hybrid films incorporating sol-gel-derived ceramics have shown strong promise as insulating dielectrics for high voltage capacitor applications. Our studies of DNA-CTMA (cetyltrimethylammonium) complex/sol-gel ceramic hybrid thin film devices have demonstrated reproducibility and stability in temperature- and frequency-dependent dielectric properties with dielectric constant k ∼ 5.0 (1 kHz), as well as reliability in DC voltage breakdown measurements, attaining values consistently in the range of 300–350 V/μm. The electrical/dielectric characteristics of DNA-CTMA films with sol-gel-derived ceramics were examined to determine the critical energy storage parameters such as voltage breakdown and dielectric constant.

Latest advances in biomaterials: from deoxyribonucleic acid to nucleobases

This paper is a review of the recent research in bio-based materials for photonics and electronics applications. Materials that we have been working with include: deoxyribonucleic acid (DNA)-based biopolymers and nucleobases. We will highlight work on increasing the ionic conductivity of DNA-based membranes, enhancing the direct (DC) current and photoconductivity of DNA-based biopolymers, crosslinking of DNA-based biopolymers and promising applications for DNA nucleobases. Key

Investigation of DNA nucleobases-thin films for potential application in electronics and photonics

In previous research we have demonstrated improvements in device performance with the incorporation of a deoxyribonucleic acid (DNA)-based biopolymer into organic light emitting diodes, organic thin film transistors and other organic photonic and electronic devices. Here, we investigate nucleobases, nitrogen-containing biological compounds found within DNA, ribonucleic acid (RNA), nucleotides and nucleosides, for use in a few of those previously investigated photonic and electronic devices. Used as an electron blocking layer in OLEDs, a gate insulator for grapheme transistors and as a dielectric in organic-based capacitors, we have produced comparable results to those using DNA-based biopolymers.

Bio-dielectrics based on DNA-Ceramic hybrid films for potential energy storage applications

The potential of DNA-based dielectrics for energy storage applications was explored via the incorporation of high dielectric constant (ε) ceramics such as TiO2 (rutile) and BaTiO3 in the DNA bio-polymer. The DNA-Ceramic hybrid films were fabricated from stable suspensions of the nanoparticles in aqueous DNA solutions. Dielectric characterization revealed that the incorporation of TiO2 (rutile) in DNA resulted in enhanced dielectric constant (14.3 at 1 kHz for 40 wt % TiO2) relative to that of DNA in the entire frequency range of 1 kHz-1 MHz. Variable temperature dielectric measurements, in the 20-80°C range, of both DNA-TiO2 and DNA-BaTiO3 films, revealed that the ceramic additive stabilizes DNA against large temperature-dependent variations in both ε and the dielectric loss factor tan δ. The bulk resistivity of the DNA-Ceramic hybrid films, in the case of both TiO2 and BaTiO3 additives in DNA, was measured to be two to three orders of magnitude higher than that of the control DNA films, indicating their potential for utilization as insulating dielectrics in capacitor applications. As a part of a baseline study, results based on a comparison of the temperature-dependent dielectric behavior of DNA and DNA-CTMA complex films as well as their frequency-dependent polarization behavior, are also discussed.

Bio-dielectric organic-inorganic hybrid films for potential energy storage applications

DNA-based bio-dielectrics incorporating sol-gel have been investigated for energy storage applications. Salmon DNA hybrid films blending sol-gel-ceramics with DNA-CTMA have potential for increased dielectric constants and higher environmental stability compared to DNA only films. Thin film capacitor devices were fabricated and characterized, showing stability in dielectric properties and reliability in voltage breakdown measurements, attaining values consistently at 300 V/um. Temperature-dependent dielectric properties as well as dielectric stability as a function of thermal cycling of these hybrid films are also discussed.

DNA hybrid dielectric film devices for energy storage and bioelectronics applications

DNA biopolymer hybrids have been investigated for energy storage applications and also as potential high k gate dielectrics in bioelectronics applications such as BioFETs. DNA-based hybrid films incorporating sol-gel-derived ceramics have shown strong promise as insulating dielectrics for high voltage capacitor applications. Our studies of DNA-CTMA complex/sol-gel hybrid thin film devices have demonstrated reproducibility and stability in temperature-and frequency-dependent dielectric properties as well as reliability in DC voltage breakdown measurements, attaining values consistently in the 300 - 350 V/um range. We have also investigated DNA-inorganic hybrids by ex situ blending of aqueous solutions of DNA with high k ceramics such as BaTiO3 and TiO2. These systems are currently being investigated as potential gate dielectrics for BioFETs by virtue of their relatively high dielectric constant, high DC electrical resistivity, and lower leakage currents than pristine DNA. Functionally layered devices have also been designed, fabricated and characterized to determine any added benefit in dielectric applications. The electrical/dielectric characteristics of DNA and DNA-CTMA with sol-gel-derived ceramics, high k ceramic fillers, and in layered devices were examined to determine their effect on vital dielectric parameters for energy storage and bioelectronics applications.

DNA-based thin-film dielectrics for potential application as gate insulators in OFETs

In this study, highly stable aqueous solutions of blends containing Deoxyribonucleic acid (DNA) and high k ceramics (BaTiO₃ or TiO₂) nanoparticles were processed. Dielectric and electrical properties of the as-prepared nanocomposites thin films were investigated. Dielectric Constant <i>k</i> values of 14 and capacitance density of 2.5 nF/cm² were achieved for a 40 wt.% BaTiO₃ loading at 1 KHz. The current-voltage (IV) measurements revealed electrical resistivity in the order of 10¹⁴ Ohm-cm with leakage current densities of the order of 10^-9 A/cm² for electric field biases up to 50V/μm.

Increasing electric field strength in polymer capacitors

Increased electric field breakdown in several polymer-based capacitor dielectrics, including biaxially oriented polypropylene, has been demonstrated using electron and hole blocking layers. Increased electric field breakdown translates into increased energy density. Presented here is work that includes using these blocking layers for a new capacitor dielectric material with a high permittivity (K). Initial results are promising, increasing the potential for even higher energy density polymer capacitors.

Novel layered architecture for high energy density capacitors (Conference Presentation)

The abstract is not available