Effects of interface energy modification in solution-processed In2O3 thin film transistors for sensing applications.

Thin film transistors (TFTs) based on metal oxides have high mobility, transparency, and excellent stability, and are considered to be a key part of the next generation transparent electronic devices. Solution-processed metal oxide thin films using the sol-gel method has enabled the deposition of metal oxide thin films without a vacuum system, and it allows metal oxide TFTs to be fabricated more efficiently at low cost and over a large area through a simple process. In this study, we fabricated In 2 O 3 using the sol-gel method and adopted various self-assembled monolayers (SAMs) to modify the interface between the semiconductor and dielectric layer. We used octadecyltrichlorosilane as a hydrophobic surface and partially removed it through exposure to UV radiation to form a patterned semiconductor using a simple spin-coating procedure that remarkably reduced the leakage current. 3-aminopropylsilane, (3-mercaptopropyl)trimethoxysilane, and cyclopentadienyltrimethylsilane as SAM materials and toluene and water as solvents to dilute them were used to modify the surface of the SiO 2 . We measured the contact angle under various conditions and the electrical characteristics of the TFTs annealed in various temperatures of 230, 250, and 300 °C to confirm the effect of interface energy modification, and concluded that surface energy affected the mobility of the In 2 O 3 transistors and the lower surface energy enhanced the mobility of the TFTs. [ABSTRACT FROM AUTHOR]