Controlling In-Ga-Zn-O thin films transport properties through density changes
Journal article, 2016

In the following study we investigate the effect of the magnetron cathode current (I-c) during reactive sputtering of In-Ga-Zn-O (a-IGZO) on thin-films nanostructure and transport properties. All fabricated films are amorphous, according to X-ray diffraction measurements. However, High Resolution Transmission Electron Microscopy revealed the a-IGZO fabricated at I-C = 70 mA to contain randomly-oriented nanocrystals dispersed in amorphous matrix, which disappear in films deposited at higher cathode current. These nanocrystals have the same composition as the amorphous matrix. One can observe that, while I-C is increased from 70 to 150 mA, the carrier mobility improves from mu(Hall) = 6.9 cm(2)/Vs to mu(Hall) = 9.1 cm(2)/Vs. Additionally, the increase of I-C caused a reduction of the depletion region trap states density of the Ru-Si-O/In-Ga-Zn-O Schottky barrier. This enhancement in transport properties is attributed to the greater overlapping of s-orbitals of the film-forming cations caused by increased density, evidenced by X-ray reflectivity, at a fixed chemical composition, regardless nanostructure of thin films. (C) 2016 Elsevier B.V. All rights reserved.

In-Ga-Zn-O

Schottky contacts

Amorphous oxide semiconductors

IGZO

Atom Probe Tomography

Author

J. Kaczmarski

Instytut Technologii Elektronowej (ITE)

Torben Boll

Chalmers, Physics, Materials Microstructure

M. A. Borysiewicz

Instytut Technologii Elektronowej (ITE)

A. Taube

Warsaw University of Technology

Instytut Technologii Elektronowej (ITE)

Mattias Thuvander

Chalmers, Physics, Materials Microstructure

Jiayan Law

Chalmers, Physics, Materials Microstructure

E. Kaminska

Instytut Technologii Elektronowej (ITE)

Krystyna Marta Stiller

Chalmers, Physics, Materials Microstructure

Thin Solid Films

0040-6090 (ISSN)

Vol. 608 57-61

Subject Categories

Materials Engineering

Physical Sciences

Areas of Advance

Materials Science

DOI

10.1016/j.tsf.2016.04.012

More information

Latest update

10/26/2018