TY - JOUR

T1 - Structural and electrical characterization of SiO2 gate dielectrics deposited from solutions at moderate temperatures in air

AU - Bin Esro, Mazran

AU - Kolosov, Oleg Victor

AU - Jones, Peter John

AU - Milne, W.I

AU - Adamopoulos, George

N1 - This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Applied Materials and Interfaces, copyright © 2016 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/acsami.6b11214

PY - 2017/1/10

Y1 - 2017/1/10

N2 - Silicon dioxide (SiO2) is the most widely used dielectric for electronic applications. It is usually produced by thermal oxidation of silicon or by using a wide range of vacuum-based techniques. By default, the growth of SiO2 by thermal oxidation of silicon, requires the use of Si substrates whereas the other deposition techniques either produce low quality or poor interface material and mostly require high deposition or annealing temperatures. Recent investigations therefore have focused on the development of alternative deposition paradigms based on solutions. Here, we report the deposition of SiO2 thin film dielectrics deposited by spray pyrolysis in air at moderate temperatures of 350 oC from pentane-2,4-dione solutions of SiCl4. SiO2 dielectrics were investigated by means of UV–Vis absorption spectroscopy, spectroscopic ellipsometry, XPS, XRD, UFM/AFM, admittance spectroscopy, and field-effect measurements. Data analysis reveals smooth (RRMS<1 nm) amorphous films with a dielectric constant of about 3.8, an optical band gap of ≈8.1 eV, leakage current densities in the order of ≈10-7 A/cm2 at 1 MV/cm and high dielectric strength in excess of 5 MV/cm. XPS measurements confirm the SiO2 stoichiometry and FTIR spectra reveal features related to SiO2 only. Thin film transistors implementing spray coated SiO2 gate dielectrics and C60 and pentacene semiconducting channels exhibit excellent transport characteristics i.e. negligible hysteresis, low leakage currents, high on/off current modulation ratio in the order of 106 and high carrier mobility.

AB - Silicon dioxide (SiO2) is the most widely used dielectric for electronic applications. It is usually produced by thermal oxidation of silicon or by using a wide range of vacuum-based techniques. By default, the growth of SiO2 by thermal oxidation of silicon, requires the use of Si substrates whereas the other deposition techniques either produce low quality or poor interface material and mostly require high deposition or annealing temperatures. Recent investigations therefore have focused on the development of alternative deposition paradigms based on solutions. Here, we report the deposition of SiO2 thin film dielectrics deposited by spray pyrolysis in air at moderate temperatures of 350 oC from pentane-2,4-dione solutions of SiCl4. SiO2 dielectrics were investigated by means of UV–Vis absorption spectroscopy, spectroscopic ellipsometry, XPS, XRD, UFM/AFM, admittance spectroscopy, and field-effect measurements. Data analysis reveals smooth (RRMS<1 nm) amorphous films with a dielectric constant of about 3.8, an optical band gap of ≈8.1 eV, leakage current densities in the order of ≈10-7 A/cm2 at 1 MV/cm and high dielectric strength in excess of 5 MV/cm. XPS measurements confirm the SiO2 stoichiometry and FTIR spectra reveal features related to SiO2 only. Thin film transistors implementing spray coated SiO2 gate dielectrics and C60 and pentacene semiconducting channels exhibit excellent transport characteristics i.e. negligible hysteresis, low leakage currents, high on/off current modulation ratio in the order of 106 and high carrier mobility.

KW - Silicon Dioxide

KW - Gate Dielectrics

KW - Solution Processed Electronics

KW - Spray Pyrolysis

KW - Thin Film Transistors

U2 - 10.1021/acsami.6b11214

DO - 10.1021/acsami.6b11214

M3 - Journal article

VL - 9

SP - 529

EP - 536

JO - ACS Applied Materials and Interfaces

JF - ACS Applied Materials and Interfaces

SN - 1944-8244

IS - 1

ER -