title: A Study on the Electrical Properties of Atomic Layer Deposition Grown InOxon Flexible Substrates with Respect to N2O Plasma Treatment and the Associated Thin-Film Transistor Behavior under Repetitive Mechanical Stress.
abstract: Indium oxide (InOx) films were deposited at low processing temperature (150 °C) by atomic layer deposition (ALD) using [1,1,1-trimethyl-N-(trimethylsilyl)silanaminato]indium (InCA-1) as the metal precursor and hydrogen peroxide (H2O2) as the oxidant. As-deposited InOxexhibits a metallic conductor-like behavior owing to a relatively high free-carrier concentration. In order to control the electron density in InOxlayers, N2O plasma treatment was carried out on the film surface. The exposure time to N2O plasma was varied (600-2400 s) to evaluate its effect on the electrical properties of InOx. In this regard, thin-film transistors (TFTs) utilizing this material as the active layer were fabricated on polyimide substrates, and transfer curves were measured. As the plasma treatment time increases, the TFTs exhibit a transition from metal-like conductor to a high-performance switching device. This clearly demonstrates that the N2O plasma has an effect of diminishing the carrier concentration in InOx. The combination of low-temperature ALD and N2O plasma process offers the possibility to achieve high-performance devices on polymer substrates. The electrical properties of InOxTFTs were further examined with respect to various radii of curvature and repetitive bending of the substrate. Not only does prolonged cyclic mechanical stress affect the device properties, but the bending direction is also found to be influential. Understanding such behavior of flexible InOxTFTs is anticipated to provide effective ways to design and achieve reliable electronic applications with various form factors.
authors: Division of Materials Science and Engineering, Hanyang University , 222 Wangsimni-ro Seongdong-gu, Seoul, 04763, Republic of Korea.
authors: Jiazhen
authors: J
authors: Sheng
authors: Department of Materials Science and Engineering, KAIST , 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.
authors: Jozeph
authors: J
authors: Park
authors: Division of Materials Science and Engineering, Hanyang University , 222 Wangsimni-ro Seongdong-gu, Seoul, 04763, Republic of Korea.
authors: Dong-Won
authors: DW
authors: Choi
authors: Display Research and Development Center, Samsung Display Company, Limited , Yongin 446-711, Republic of Korea.
authors: Junhyung
authors: J
authors: Lim
authors: Division of Materials Science and Engineering, Hanyang University , 222 Wangsimni-ro Seongdong-gu, Seoul, 04763, Republic of Korea.
authors: Jin-Seong
authors: JS
authors: Park
keywords: N2O plasma treatment; atomic layer deposition; flexible TFT; indium oxide semiconductor; mechanical stress