carbon nanotubes as injection electrodes for tfts
DESCRIPTION
Kevin WangNanofabrication Seminar2008/4/27. Carbon Nanotubes as Injection Electrodes for TFTs. Concept. Aguirre, C.M., Martel, R. et al. Engineering Physics, EP Montréal Chemistry, U. of Montréal Backgated. Thin Film. Pentacene Island. Fabrication – Island. Double-wall nanotubes - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Carbon Nanotubes as Injection Electrodes for TFTs](https://reader036.vdocuments.us/reader036/viewer/2022062323/56815c53550346895dca53ae/html5/thumbnails/1.jpg)
Carbon Nanotubes as Injection Electrodes for TFTsKevin Wang Nanofabrication Seminar2008/4/27
![Page 2: Carbon Nanotubes as Injection Electrodes for TFTs](https://reader036.vdocuments.us/reader036/viewer/2022062323/56815c53550346895dca53ae/html5/thumbnails/2.jpg)
Concept
Aguirre, C.M., Martel, R. et al. Engineering Physics, EP Montréal Chemistry, U. of Montréal
Backgated Pentacene
Island Thin Film
![Page 3: Carbon Nanotubes as Injection Electrodes for TFTs](https://reader036.vdocuments.us/reader036/viewer/2022062323/56815c53550346895dca53ae/html5/thumbnails/3.jpg)
Fabrication – Island
Double-wall nanotubes Form gaps - electrical breakdown
Contacts – optical lithography Ti and Pd by e-beam evaporation Anneal (vacuum) 550°C, 1h
Post-Breakdown
![Page 4: Carbon Nanotubes as Injection Electrodes for TFTs](https://reader036.vdocuments.us/reader036/viewer/2022062323/56815c53550346895dca53ae/html5/thumbnails/4.jpg)
Fabrication – Island (cont.) Spin-coat precursor
2 mg/mL chloroform solution 13,6-N-sulfinylacetamido-
pentacene Converts to pentacene
(170-200°C)
Asymmetric CNT – Pd
![Page 5: Carbon Nanotubes as Injection Electrodes for TFTs](https://reader036.vdocuments.us/reader036/viewer/2022062323/56815c53550346895dca53ae/html5/thumbnails/5.jpg)
Fabrication – TFT
SWNTs (10 nanotubes/μm2)
Ti contacts, optical Lithography, liftoff Sonicate free nanotubes Anneal (vacuum) 550°C, 1h
Pentacene (50nm) Vacuum sublimation (0.2nm/s)
![Page 6: Carbon Nanotubes as Injection Electrodes for TFTs](https://reader036.vdocuments.us/reader036/viewer/2022062323/56815c53550346895dca53ae/html5/thumbnails/6.jpg)
Fabrication – TFT (cont.)
W/L = 200μm/20μm Au or Ti, 30 nm thick
![Page 7: Carbon Nanotubes as Injection Electrodes for TFTs](https://reader036.vdocuments.us/reader036/viewer/2022062323/56815c53550346895dca53ae/html5/thumbnails/7.jpg)
Performance – Island
40 nm gap device Ion/Ioff = 100 Ion = 2nA (Vds = 8V)
Superlinear IV Poor gate control tox = 20 nm
Subthreshold Swing 1.3V/dec
![Page 8: Carbon Nanotubes as Injection Electrodes for TFTs](https://reader036.vdocuments.us/reader036/viewer/2022062323/56815c53550346895dca53ae/html5/thumbnails/8.jpg)
Asymmetric CNT-Pd
Injection from CNT side 21x more current CNT good emitter, poor collector?
![Page 9: Carbon Nanotubes as Injection Electrodes for TFTs](https://reader036.vdocuments.us/reader036/viewer/2022062323/56815c53550346895dca53ae/html5/thumbnails/9.jpg)
Performance - TFT
CNT array – ideal linear behavior Au, Ti – nonlinear, large contact
barriers
Barrier at CNTlowered by E-field enhancement Molecular energy shift
![Page 10: Carbon Nanotubes as Injection Electrodes for TFTs](https://reader036.vdocuments.us/reader036/viewer/2022062323/56815c53550346895dca53ae/html5/thumbnails/10.jpg)
Performance – TFT (cont.)
![Page 11: Carbon Nanotubes as Injection Electrodes for TFTs](https://reader036.vdocuments.us/reader036/viewer/2022062323/56815c53550346895dca53ae/html5/thumbnails/11.jpg)
Conclusion
Carbon nanotubes enhance transistor current
Effective barrier lowering at CNT-Pentacene interface
![Page 12: Carbon Nanotubes as Injection Electrodes for TFTs](https://reader036.vdocuments.us/reader036/viewer/2022062323/56815c53550346895dca53ae/html5/thumbnails/12.jpg)
Additional
Ti contacts