Electronic Transport Properties of Chemical Gas Sensor Using Conducting Polymer PAni

Abstract:

The conducting polymer PAni is coated on Au electrode sample by spin coater on 500rpm and 3000rpm for 5sec and 30sec. Then, it was drying 10min at 180
C. The layer thickness was 140~200nm. The electrodes were fabricated the resist pattern by electron beam writing machine which was performed on a Raith75 e-Line on the PMMA 950K, thickness 100nm. The electrodes were written at an electron does of 200uAs/cm2 and developed for 40sec in a 1:3 MIBK (methyl-isobutyl-ketone): IPA (isopropyl alcohol) solution. Metal lift-off of the PMMA in acetone was preceded by an e-beam evaporation consisting of 50Å Cr and 250Å Au. Electrical measurements were performed on low-noise commercial probe stations equipped. We measured distance between the electrodes ranges from a few tens of nanometer to hundreds nanometer by AFM (Atomic Force Microscopy) which was done with silicon tips in non-contact mode on a PSIA, XE-100.

• Periodical: Key Engineering Materials (Volumes 326-328)
• Pages: 1363-1366
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.326-328.1363
• Online since: December 2006
• Authors: Jae Jong Lee, Soo Yeon Park, Seung Woo Lee, In Deok Jeon
• Keywords: Conducting Polymer, Electron Beam Lithography, Gas Sensor, NH₃, PANI

References

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[2] A.B. Kaiser, et al, Electronic Transport Properties of Conducting Polymers and Polymer Blends, Synthetic Metals, Vol. 69, (1995).

DOI: 10.1016/0379-6779(94)02415-u

[3] C.O. Yoon, et al, Transports in Blends of Conducting Polymers, Synthetic Metals, Vol. 69, (1995).

[4] B. Adhikari, et al, Polymers in Sensor Applications, Prog. Polymer. Sci., Vo. 29, 2004 Fig. 1 The procedure of electrode fabrication Fig. 2 The fabrication procedure of the chemo using photolithography. sensor using the electron-beam lithography. Table 1. The properties of the conducting polymer. Item Properties Conductivity 2x10 -2s/cm Particle size <100nm Aniline unit : sulfonic acid 1: 2 Solid content 4% Viscosity 3 mPa*s (a) SEM image (b) AFM image Fig. 3 SEM and AFM images for fabricated functional nanostructure of the chemical sensor -0. 000010 -0. 000005 0. 000000 0. 000005 0. 000010 140 160 180 200 220 240 260 280 300 320 340 360 380 400 420 440 460 480 Resistance (ohm) Current Source (A) N2 NH3 -0. 000010 -0. 000005 0. 000000 0. 000005 0. 000010.

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0065 Conductance (1/ohm) Current Source (A) N2 NH3 � Fig. 4 Measured results for the resistance and the conductance with 80nm clearance � -0. 000010 -0. 000005 0. 000000 0. 000005 0. 000010 -0. 0005.

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0045 Conductivity (1/ohm) Current Source (A) 80nm 800nm 1000nm � Fig. 5 Variations of conductance with respect to the clearance between electrodes � -0. 000010 -0. 000005 0. 000000 0. 000005 0. 000010 100 200 300 400 500 600 Resistance (ohm) Current Source (A) before NH3 after -0. 000010 -0. 000005 0. 000000 0. 000005 0. 000010.

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0065 Conductivity (1/ohm) Current Source (A) before NH3 after � Fig. 6 Experiment results for the recovery test of the conducting polymer on NH3 gas.