TY - JOUR
T1 - Parasitic Capacitance Effect on Dynamic Performance of Aerosol-Jet-Printed Sub 2 v Poly(3-hexylthiophene) Electrolyte-Gated Transistors
AU - Zare Bidoky, Fazel
AU - Frisbie, C. Daniel
N1 - Publisher Copyright:
© 2016 American Chemical Society.
PY - 2016/10/12
Y1 - 2016/10/12
N2 - Printed, low-voltage poly(3-hexylthiophene) (P3HT) electrolyte-gated transistors (EGTs) have favorable quasi-static characteristics, including sub 2 V operation, carrier mobility (μ) of 1 cm2/(V s), ON/OFF current ratio of 106, and static leakage current density of 10-6 A/cm2. Here we study the dynamic performance of P3HT EGTs in which the semiconductor, dielectric, and gate electrode were deposited using aerosol-jet printing; the source and drain electrodes were patterned by conventional microlithography. With a source-to-drain separation of 2.5 μm, the highest theoretical achievable switching frequency is ∼10 MHz, assuming the movement of charge through the semiconductor is the limiting step. However, the measured maximum switching frequency of P3HT EGTs to date is ∼1 kHz, implying that another process is slowing the response. By systematically varying the device geometry, we show that the frequency is limited by the capacitance between the gate and drain (i.e., parasitic capacitance). The traditional scaling of switching time with the square of channel length (L) does not hold for P3HT EGTs. Rather, minimizing the size of the drain electrode increases the maximum switching speed. We achieve 10 kHz for P3HT EGTs with source/drain electrode dimensions of 2.5 μm × 50 μm and channel dimensions of 2.5 μm × 50 μm. Further improvements will require additional shrinkage of electrode dimensions as well as consideration of other factors such as ion gel thickness and carrier mobility.
AB - Printed, low-voltage poly(3-hexylthiophene) (P3HT) electrolyte-gated transistors (EGTs) have favorable quasi-static characteristics, including sub 2 V operation, carrier mobility (μ) of 1 cm2/(V s), ON/OFF current ratio of 106, and static leakage current density of 10-6 A/cm2. Here we study the dynamic performance of P3HT EGTs in which the semiconductor, dielectric, and gate electrode were deposited using aerosol-jet printing; the source and drain electrodes were patterned by conventional microlithography. With a source-to-drain separation of 2.5 μm, the highest theoretical achievable switching frequency is ∼10 MHz, assuming the movement of charge through the semiconductor is the limiting step. However, the measured maximum switching frequency of P3HT EGTs to date is ∼1 kHz, implying that another process is slowing the response. By systematically varying the device geometry, we show that the frequency is limited by the capacitance between the gate and drain (i.e., parasitic capacitance). The traditional scaling of switching time with the square of channel length (L) does not hold for P3HT EGTs. Rather, minimizing the size of the drain electrode increases the maximum switching speed. We achieve 10 kHz for P3HT EGTs with source/drain electrode dimensions of 2.5 μm × 50 μm and channel dimensions of 2.5 μm × 50 μm. Further improvements will require additional shrinkage of electrode dimensions as well as consideration of other factors such as ion gel thickness and carrier mobility.
KW - aerosol-jet printing
KW - cut-off frequency
KW - dynamic performance
KW - electrolyte-gated transistors
KW - ion gel
KW - parasitic capacitance
KW - poly(3-hexylthiophene)
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U2 - 10.1021/acsami.6b08396
DO - 10.1021/acsami.6b08396
M3 - Article
C2 - 27641063
AN - SCOPUS:84991738114
SN - 1944-8244
VL - 8
SP - 27012
EP - 27017
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 40
ER -