1. Speaker: Wen-Fan Liao ID:g946220
ELECTRICAL AND ELECTROMECHANICAL CHARACTERISTICS OF NANOASSEMBLED CARBON NANOTUBE THIN FILM RESISTORS ON FLEXIBLE SUBSTRATES Wei Xue and Tianhong Cui Department of Mechanical Engineering, University of Minnesota, Minneapolis, USA Transducers’07
Speaker: Wen-Fan Liao
ID:g946220

2. Outline Introduction Experiments Device Characteristics Conclusion
References

3. Introduction
This paper report the fabrication of single-walled carbon nanotube (SWNT) thin-film on plastic substrates with layer-by-layer self-assembly
assemble SWNTs on flexible substrates and explore the properties of the SWNT thin films which are built with alternating layers of SWNTs and PDDA

4. Experiments Layer-by-layer self-assembly of polyelectrolytes/CNTs and
naonoparticles
Ref : T Cui and W Xue, “Assembling three-dimensional carbon nanotube-based cantilever arrays,” SPIE Newsroom 2007
Layer-by-layer self-assembly of polyelectrolytes/CNTs and
polyelectrolytes/nanoparticles

5. Experiments (PDDA/PSS)2 (PDDA/SWNT)n
Ref : W Xue and T Cui, “Deposition and characterization of layer-by-layer nano selfassembled carbon nanotube multilayer thin films” IEEE NEMS 2007
1μm
(a) Structure of self-assembled SWNT multilayer thin film
(b) SEM image of assembled SWNTs

6. Experiments
Cr/Au
Ref : W Xue and T Cui, “Deposition and characterization of layer-by-layer nano selfassembled carbon nanotube multilayer thin films” IEEE NEMS 2007
Schematic structure of a SWNT thin-film resistor built on a flexible substrate

7. Experiments (a) Flexed transparency film with prepatterned electrodes
(b) Transparency coated with 5 layers of SWNTs

8. Experiments 4156A Precision Semiconductor Parameter Analyzer
up to four probes
Measurements include I-V curve, Id-Vg graphs, etc
Ref :

9. Device Characteristics
6.37MΩ
0.37MΩ
0.30MΩ
0.21MΩ
0.14MΩ
R10 =6.37 MΩ
R0 =1.35 MΩ
Rn =(R0×R10)/[R0+(n-10) ×R10]
Characteristics of SWNT thin-film resistors on flexible substrates

10. Device Characteristics
G14 = △R14/R14 = 38.2%
G16 = △R16/R16 = 47.1%
Resistance versus mechanical deformation of SWNT thin-film resistors

11. Device Characteristics
Schematic models for axial deformation of SWNT on different topographies

12. Conclusion
demonstrated the fabrication and characterization of SWNT multilayer thin films on flexible substrates
MEMS/NEMS devices such as pressure sensors, accelerometers, and magnetic sensors have the potential to be developed and fabricated

13. References
Wei Xue and Tianhong Cui, “Electrical and electromechanical characteristics of nano-assembled carbon nanotube thin film resistors on flexible substrates,” Transducers’07, Lyon, France, June 2007
Wei Xue and Tianhong Cui, “Deposition and characterization of layer-by-layer nano selfassembled carbon nanotube multilayer thin films,” IEEE NEMS 2007, Bangkok, Thailand, pp , January 2007
Tianhong Cui and Wei Xue, “Assembling three-dimensional carbon nanotube-based cantilever arrays,” The International Society for Optical Engineering - SPIE Newsroom - Micro/Nano Lithography & Fabrication, DOI: / , 2007

14. ~Thank you for your attention~