Johannes Kepler Univ. of Linz & Inst. of Problems of Chemical Physics of Russian: Fabrication of “green” organic field-effect transistors N. Marjanovic M. Irimia-Vladu and colleagues from the Johannes Kepler University of Linz & Institute of Problems of Chemical Physics of Russian present this work in the frame of the “green potentiality” of organic electronics. They
have succeeded to fabricate OTFTs with nature-based materials such as caramelized glucose, edible hard gelatin and commercially
Steps towards
available plastics based on potato and corn starch acting as
green electronics
substrates. Dielectrics are chosen among naturally occurring nucleobases, such as adenine and guanine, as well as various sugars
(glucose, lactose, sucrose) or even caffeine. Last but not least, glucose, adenine, and guanine employed as dielectrics show remarkable properties, with low dielectric losses (10-2 at 10 mHz for adenine and guanine; 10-1 at 10 mHz for glucose) and high breakdown strengths (between 1.5 to 3.5 MV cm-1) respectively. Finally, beta-carotene and indigo are employed as natural p- and n-type organic semiconductors.
The transistors demonstrate operational voltages as low as 4–5 V, a source drain current of up to 0.5 µA and an on-off ratio of 3–5 orders of magnitude have been fabricated with such materials. The Figure 2 present the characteristics of an edible OFET built on an aurin coated gelatin capsule substrate with an operating voltage of 20 V and an on-off ratio of 105.
Figure 1: a,b) Transfer and output characteristics of an OFET on a biodegradable Ecoflex substrate; the roughness of the Ecoflex foil is reduced with a smoothing layer of aurin. The transfer curve displays the temporal stability of the transistor characteristics after 1000 continuous scan cycles in 12 hours; Adenine forms the dielectric and perylene diimide is the semiconductor; μ = 0.01 cm 2V− 1s−1; C0d = 3.1 nF cm-2; c,d) Transfer and output characteristics of an OFET with an Inorganic (aluminium oxide)-organic (0.25 nm evaporated glucose) gate dielectric and perylene diimide as organic semiconductor; μ = 0.01 cm 2V− 1s−1; ; C0d = 138.8 nF cm-2.
This work is a proof of principle that organic electronics has huge potential for developing biodegradable, biocompatible, bioresorbable, or even metabolizable products. By using natural products to fabricate devices, the authors have started to pave a way to real “green electronics”.
This work comprises steps towards environmentally safe devices in low cost, large volume, disposable or throwaway electronic applications, such as in food packaging, plastic bags, and disposable dishware. In addition, there is significant potential to use such electronic items in biomedical implants.
Figure 2: a, b) Transfer and output characteristics of an edible OFET on a hard gelatin capsule substrate; the roughness of the substrate foil is reduced with a smoothing layer of aurin. Adenine and guanine form the gate dielectric and perylene diimide is the organic semiconductor; μ = 0.02 cm2V−1s−1 ; C0d = 5.1 nF m− 2. Reprinted with permission from Advanced Functional Materials
"Biocompatible and Biodegradable Materials for Organic Field-Effect Transistors" ; M.
Irimia-Vladu, P.A. Troshin, M. Reisinger, L. Shmygleva, Y. Kanbur, G. Schwabegger, M.
Bodea, R. Schwödiauer, A. Mumyatov, J.W. Fergus, V.F. Razumov, H. Sitter, N.S. Sariciftci, S.
Bauer : Advanced Functional Materials20, 4069 (2010).
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