Supporting Information Fabrication of High-Performance Ultrathin ...
Supporting Information Fabrication of High-Performance Ultrathin In2O3 Film Field-Effect Transistors and Biosensors Using Chemical Lift-Off Lithography
Jaemyung Kim,†,‡,# You Seung Rim,†,§,# Huajun Chen,†,§ Huan H. Cao,†,‡ Nako Nakatsuka,†,‡ Hannah L. Hinton,†,‡ Chuanzhen Zhao,†,‡,� Anne M. Andrews,*,†,‡,± Yang Yang,*,†,§ and Paul S. Weiss*,†,‡,§
California NanoSystems Institute, University of California, Los Angeles, Los Angeles, California 90095, United States
†
Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095, United States ‡
Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, California 90095, United States §
Department of Materials Science and Engineering, Beijing Institute of Technology, Beijing, China 100081 �
Department of Psychiatry and Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, California 90095, United States ±
*To whom correspondence should be addressed: [email protected] (A. M. A.); [email protected] (Y. Y.); [email protected] (P. S. W.)
Figure S1. Field-effect transistor device patterns on a SiO2/Si substrate produced by chemical lift-off lithography with a short processing time (5 min self-assembled monolayer deposition, 5 min stamping process).
Figure S2. Scanning electron microscope images of channel regions. (a) A representative source-drain electrode pair used for device fabrication. (b) A transmission line measurement (TLM) pattern with varying channel lengths.
S1
Figure S3. Bottom-gate bottom-contact field-effect transistor transfer characteristics of ultrathin In2O3 layers annealed at (a) 200 °C, (b) 250 °C, and (c) 300 °C for 1 h.
Coating Method
Channel Thickness (nm)
µsat (cm V-1 s-1)
ION/IOFF
12
107
Sol–gel
30
0.7
Sol–gel
25
Sol–gel
Sol–gel
4
2
SS (V dec-1)
Ref.
1.6
Our work
106
5.7
S1
2.24
108
0.45
S2
6
7.5
107
N/A
S3
Sol–gel
30
3.37
107
N/A
S4
Sputtering
8
15.3
108
0.25
S5
Sputtering
10
15
106
N/A
S6
Table S1. Device performance of previously reported In2O3 field-effect transistors.
S2
Figure S4. Bottom-gate top-contact field-effect transistor (a) transfer and (b) output characteristics of ultrathin In2O3 layers.
Annealing Temperature (°C)
µsat (cm V-1 s-1)
ION/IOFF
2.3 ± 0.2
~106
1.2 ± 0.1
19.5 ± 2.1
BGBC
250
11.5 ± 1.3
~107
1.6 ± 0.1
15.6 ± 2.0
BGBC
300
10.4 ± 1.8
~107
2.7 ± 0.9
18.2 ± 1.2
BGTC
250
12.1 ± 3.5
~108
0.9 ± 0.2
9.5 ± 2.7
Geometry BGBC
a
Threshold voltage
200
2
SS (V dec-1)
Table S2. Summary of In2O3 field-effect transistor device performance.
S3
Vth (V)a
Figure S5. Scanning electron microscope images of submicrometer-channel devices with gap lengths measuring (b) 300 nm and (c) 150 nm.
S4
Figure S6. Cyclic voltammogram of a Pt wire in 0.1× PBS with (red: CDA = 1 mM, green: CDA = 1 µM) or without (blue) dopamine.
S5
Figure S7. Transfer characteristics of devices with (green) or without (blue) the In2O3 channel layer, confirming that the leakage current through a liquid electrolyte (blue) is negligible.
S6
Figure S8. Transfer characteristics of In2O3 field-effect transistors without aptamer immobilization. For CDA ≥1 µM, non-specific binding of dopamine on the channel surface becomes significant and causes upward shift in the drain current even without aptamer functionalization. No significant change in drain current was observed for CDA
Jaemyung Kim,†,‡,# You Seung Rim,†,§,# Huajun Chen,†,§ Huan H. Cao,†,‡ Nako Nakatsuka,†,‡ Hannah L. Hinton,†,‡ Chuanzhen Zhao,†,‡,� Anne M. Andrews,*,†,‡,± Yang Yang,*,†,§ and Paul S. Weiss*,†,‡,§
California NanoSystems Institute, University of California, Los Angeles, Los Angeles, California 90095, United States
†
Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095, United States ‡
Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, California 90095, United States §
Department of Materials Science and Engineering, Beijing Institute of Technology, Beijing, China 100081 �
Department of Psychiatry and Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, California 90095, United States ±
*To whom correspondence should be addressed: [email protected] (A. M. A.); [email protected] (Y. Y.); [email protected] (P. S. W.)
Figure S1. Field-effect transistor device patterns on a SiO2/Si substrate produced by chemical lift-off lithography with a short processing time (5 min self-assembled monolayer deposition, 5 min stamping process).
Figure S2. Scanning electron microscope images of channel regions. (a) A representative source-drain electrode pair used for device fabrication. (b) A transmission line measurement (TLM) pattern with varying channel lengths.
S1
Figure S3. Bottom-gate bottom-contact field-effect transistor transfer characteristics of ultrathin In2O3 layers annealed at (a) 200 °C, (b) 250 °C, and (c) 300 °C for 1 h.
Coating Method
Channel Thickness (nm)
µsat (cm V-1 s-1)
ION/IOFF
12
107
Sol–gel
30
0.7
Sol–gel
25
Sol–gel
Sol–gel
4
2
SS (V dec-1)
Ref.
1.6
Our work
106
5.7
S1
2.24
108
0.45
S2
6
7.5
107
N/A
S3
Sol–gel
30
3.37
107
N/A
S4
Sputtering
8
15.3
108
0.25
S5
Sputtering
10
15
106
N/A
S6
Table S1. Device performance of previously reported In2O3 field-effect transistors.
S2
Figure S4. Bottom-gate top-contact field-effect transistor (a) transfer and (b) output characteristics of ultrathin In2O3 layers.
Annealing Temperature (°C)
µsat (cm V-1 s-1)
ION/IOFF
2.3 ± 0.2
~106
1.2 ± 0.1
19.5 ± 2.1
BGBC
250
11.5 ± 1.3
~107
1.6 ± 0.1
15.6 ± 2.0
BGBC
300
10.4 ± 1.8
~107
2.7 ± 0.9
18.2 ± 1.2
BGTC
250
12.1 ± 3.5
~108
0.9 ± 0.2
9.5 ± 2.7
Geometry BGBC
a
Threshold voltage
200
2
SS (V dec-1)
Table S2. Summary of In2O3 field-effect transistor device performance.
S3
Vth (V)a
Figure S5. Scanning electron microscope images of submicrometer-channel devices with gap lengths measuring (b) 300 nm and (c) 150 nm.
S4
Figure S6. Cyclic voltammogram of a Pt wire in 0.1× PBS with (red: CDA = 1 mM, green: CDA = 1 µM) or without (blue) dopamine.
S5
Figure S7. Transfer characteristics of devices with (green) or without (blue) the In2O3 channel layer, confirming that the leakage current through a liquid electrolyte (blue) is negligible.
S6
Figure S8. Transfer characteristics of In2O3 field-effect transistors without aptamer immobilization. For CDA ≥1 µM, non-specific binding of dopamine on the channel surface becomes significant and causes upward shift in the drain current even without aptamer functionalization. No significant change in drain current was observed for CDA
