Device Applications of
Semiconducting SWNTs
Jeong-O Lee
Korea Research Institute of
Chemical Technology
Nanomaterials Research Team
Applications of SWNT-FET in KRICT
1. Gas sensors
200
1% NH3 on
850
I(nA)
I(nA)
150
100
50
0
1000
200 ppm NO2 on
2000
3000
4000
0
5000
50
100
150
200
Time(s)
Time(s)
800
Peroxidase
Peroxidase with ABTS
ABTS in600
500
400
Isd(nA)
2. Biosensors
750
200
0
-200
400
-400
I(nA)
0
800
-0.10
-0.05
0.00
0.05
0.10
Vsd(V)
300
200
0
100
200
300
400
500
Time(s)
Nanomaterials Research Team
Fabrication of high performance
SWNT-FET
Problems in SWNT-based electronic devices
1. Chirality control is not possible
2. Reproducibility of the individual devices is poor
3. Stability of the devices
1. Chirality control?
10
Before the diazonium
reaction
After the first reaction
60
1
Second reaction
I(µA)
I (µA)
40
20
0.1
0.01
Third reaction
0
0
5
10
bias(V)
15
20
0.001
-10
-5
0
5
10
Vg (V)
Nanomaterials Research Team
Fabrication of FET with metallic SWNT
-- - --- - - --
+++++
+
++ ++
+++
Vg > 0
Vg < 0
Vg
10
250
8
200
6
150
I(nA)
I(nA)
Contact barrier control
with charged proteinnanoparticles
I
4
100
2
50
CNT
CNT with strepavidin
0
-4
-2
0
Vbg(V)
2
4
0
-2
0
2
4
Vbg(V)
Nanomaterials Research Team
Effect of humidity on SWNT-FETs
60
0
-30
800
dI/dV(nS)
Isd(nA)
30
35% RH
40% RH
45% RH
50% RH
55% RH
60% RH
65% RH
70% RH
-60
600
400
-90
-0.10
30
40
50
60
70
80
humidity(%)
-0.05
0.00
0.05
0.10
Vsd(V)
Water molecules can dope carbon nanotubes; At full coverage,
0.007e/H2O will be donated to the tube
Nanomaterials Research Team
Effective p-doing of SWNT-FET with
SU-8
(a)
4
2
SU-8 coated SWNT-FET
bare SWNT-FET
3
SU-8 coated SWNT-FET
bare SWNT-FET
2
1
1
I(µA)
I(µA)
(b)
0
0
-1
-2
-1
-3
-2
-1.0
-0.5
0.0
Vbg(V)
0.5
1.0
-4
-10
-5
0
5
10
Vbg(V)
Nanomaterials Research Team
Acknowledgement
Hye-Mi So, Hyunju Chang, Ki-jeong Kong, Youngmin Choi, and Beoyong
Whan Ryu in KRICT
Byung-Kye Kim and Ju-Jin Kim
Chonbuk National University
Pil Sun Na and Hyojin Kim
Chungnam National University
Nanomaterials Research Team