Gupta, Swati and Gleskova, Helena (2013) Optimizing the deposition rate of vacuum-grown n-octylphosphonic acid monolayer for low-voltage thin-film transistors. SID Symposium Digest of Technical Papers, 44 (Supple). pp. 135-138.
Gupta_Gleskova_SDTP_2013_Optimizing_the_deposition_rate_of_vacuum_grown_n_octylphosphonic_acid.pdf - Accepted Author Manuscript
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A self-assembled monolayer of n-octylphosphonic acid (C8PA) is prepared from vapor phase in vacuum. C8PA thickness corresponding to several monolayers is deposited on aluminum oxide (AlOx) and subsequently heated to leave a monolayer of chemisorbed molecules. The effect of C8PA deposition rate on a 15-nm-thick, bilayer AlOx/C8PA dielectric and low-voltage p-channel organic thin-film transistors (OTFTs) is studied. The increase in the deposition rate from 0.1 to 7.0 Å/s leads to increase in the field-effect mobility from 0.039 to 0.061 cm2/Vs, while the threshold voltage remains around −1.55 V. At the same time, the off-current is reduced from 2.3 × 10−12 to 1.3 × 10−12A, the subthreshold slope is lowered from 100 to 89 mV/decade and the on/off current ratio is increased from ∼105 to ∼106. The leakage current density of AlOx is reduced from 1 × 10−7 to 4 × 10−8 A/cm2 at 3 V when C8PA monolayer is added on top of it. In addition, pentacene grain size on AlOx/C8PA is larger than that on AlOx. The overall performance of AlOx/C8PA OTFTs is superior to that of AlOx OTFTs.
|Keywords:||low-voltage thin-film transistors, optimizing the deposition rate, vacuum-grown, n-octylphosphonic acid monolayer, Electrical engineering. Electronics Nuclear engineering, Electrical and Electronic Engineering|
|Subjects:||Technology > Electrical engineering. Electronics Nuclear engineering|
|Department:||Faculty of Engineering > Electronic and Electrical Engineering|
|Depositing user:||Pure Administrator|
|Date Deposited:||11 Apr 2014 10:46|
|Last modified:||01 Apr 2017 09:20|