Open AccessAnalysis of Ultrahigh Apparent Mobility in Oxide Field‐Effect Transistors
Author(s) -
Chen Changdong,
Yang BoRu,
Li Gongtan,
Zhou Hang,
Huang Bolong,
Wu Qian,
Zhan Runze,
Noh YongYoung,
Minari Takeo,
Zhang Shengdong,
Deng Shaozhi,
Sirringhaus Henning,
Liu Chuan
Publication year - 2019
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.201801189
Subject(s) - transistor , materials science , optoelectronics , field effect transistor , thin film transistor , oxide , electron mobility , semiconductor , x ray photoelectron spectroscopy , doping , nanotechnology , analytical chemistry (journal) , chemistry , layer (electronics) , electrical engineering , physics , nuclear magnetic resonance , voltage , chromatography , metallurgy , engineering
For newly developed semiconductors, obtaining high‐performance transistors and identifying carrier mobility have been hot and important issues. Here, large‐area fabrications and thorough analysis of InGaZnO transistors with enhanced current by simple encapsulations are reported. The enhancement in the drain current and on–off ratio is remarkable in the long‐channel devices (e.g., 40 times in 200 µm long transistors) but becomes much less pronounced in short‐channel devices (e.g., 2 times in 5 µm long transistors), which limits its application to the display industry. Combining gated four‐probe measurements, scanning Kelvin‐probe microscopy, secondary ion mass spectrometry, X‐ray photoelectron spectroscopy, and device simulations, it is revealed that the enhanced apparent mobility up to several tens of times is attributed to the stabilized hydrogens in the middle area forming a degenerated channel area while that near the source‐drain contacts are merely doped, which causes artifact in mobility extraction. The studies demonstrate the use of hydrogens to remarkably enhance performance of oxide transistors by inducing a new mode of device operation. Also, this study shows clearly that a thorough analysis is necessary to understand the origin of very high apparent mobilities in thin‐film transistors or field‐effect transistors with advanced semiconductors.