Li-Assisted Low-Temperature Phase Transitions in Solution-Processed Indium Oxide Films for High-Performance Thin Film Transistor.
Lithium (Li)-assisted indium oxide (In2O3) thin films with ordered structures were prepared on solution-processed zirconium oxide (ZrO2) gate dielectrics by spin-casting and thermally annealing hydrated indium nitrate solutions with different Li nitrate loadings. It was found that the Li-assisted In precursor films on ZrO2 dielectrics could form crystalline structures even at processing temperatures (T) below 200 °C. Different In oxidation states were observed in the Li-doped films, and the development of such states was significantly affected by both temperature and the mol% of Li cations, [Li(+)]/([In(3+)] + [Li(+)]), in the precursor solutions. Upon annealing the Li-assisted precursor films below 200 °C, metastable indium hydroxide and/or indium oxyhydroxide phases were formed. These phases were subsequently transformed into crystalline In2O3 nanostructures after thermal dehydration and oxidation. Finally, an In2O3 film doped with 13.5 mol% Li(+) and annealed at 250 °C for 1 h exhibited the highest electron mobility of 60 cm(2) V(-1) s(-1) and an on/off current ratio above 10(8) when utilized in a thin film transistor.
Department of Materials Science and Engineering, Inha University, Incheon 402-751, Republic of Korea.
Manh-Cuong
MC
Nguyen
Department of Applied Organic Materials Engineering, Inha University, Incheon 402-751, Republic of Korea.
Mi
M
Jang
Department of Materials Science and Engineering, Inha University, Incheon 402-751, Republic of Korea.
Dong-Hwi
DH
Lee
Department of Materials Science and Engineering, Inha University, Incheon 402-751, Republic of Korea.
Hyun-Jun
HJ
Bang
Department of Applied Organic Materials Engineering, Inha University, Incheon 402-751, Republic of Korea.
Minjung
M
Lee
Department of Electronic Engineering, Hanyang University, Seoul 133-791, Republic of Korea.
Jae Kyeong
JK
Jeong
Department of Applied Organic Materials Engineering, Inha University, Incheon 402-751, Republic of Korea.
Hoichang
H
Yang
Department of Materials Science and Engineering, Inha University, Incheon 402-751, Republic of Korea.
Rino
R
Choi