Nondegenerate Polycrystalline Hydrogen-Doped Indium Oxide (InOx:H) Thin Films Formed by Low-Temperature Solid-Phase Crystallization for Thin Film Transistors

Materials

卷:15

Hisao Makino¹  Yusaku Magari²  Mamoru Furuta³  Taiki Kataoka³ 

[1]Center for Nanotechnology, Research Institute, Kochi University of Technology, Kami 782-8502, Kochi, Japan

[2]|Graduate School of Natural Science and Technology, Shimane University, Matsue 690-8504, Shimane, Japan

[3]|Materials Science and Engineering Course, Kochi University of Technology, Kami 782-8502, Kochi, Japan

关键词: indium oxide;    thin film transistor;    solid-phase crystallization;    metal–insulator transition;   

DOI  :  10.3390/ma15010187

来源: DOAJ

【 摘 要 】

We successfully demonstrated a transition from a metallic InO_x film into a nondegenerate semiconductor InO_x:H film. A hydrogen-doped amorphous InO_x:H (a-InO_x:H) film, which was deposited by sputtering in Ar, O₂, and H₂ gases, could be converted into a polycrystalline InO_x:H (poly-InO_x:H) film by low-temperature (250 °C) solid-phase crystallization (SPC). Hall mobility increased from 49.9 cm²V⁻¹s⁻¹ for an a-InO_x:H film to 77.2 cm²V⁻¹s⁻¹ for a poly-InO_x:H film. Furthermore, the carrier density of a poly-InO_x:H film could be reduced by SPC in air to as low as 2.4 × 10¹⁷ cm⁻³, which was below the metal–insulator transition (MIT) threshold. The thin film transistor (TFT) with a metallic poly-InO_x channel did not show any switching properties. In contrast, that with a 50 nm thick nondegenerate poly-InO_x:H channel could be fully depleted by a gate electric field. For the InO_x:H TFTs with a channel carrier density close to the MIT point, maximum and average field effect mobility (μ_FE) values of 125.7 and 84.7 cm²V⁻¹s⁻¹ were obtained, respectively. We believe that a nondegenerate poly-InO_x:H film has great potential for boosting the μ_FE of oxide TFTs.

【 授权许可】

Unknown