The Structure and Properties of Amorphous Indium Oxide

Area of Science:

• Materials Science
• Solid State Physics
• Thin Film Technology

Background:

• Indium oxide (In2O3) is a crucial transparent conductive oxide.
• Understanding the structure-property relationship in In2O3 thin films is vital for device applications.
• The amorphous-to-crystalline transition influences the electronic properties of In2O3.

Purpose of the Study:

• To investigate the amorphous-to-crystalline transition in In2O3 thin films grown by pulsed laser deposition.
• To elucidate the structure of amorphous In2O3 and its impact on transport properties.
• To establish a structure-property relationship across different In2O3 film morphologies.

Main Methods:

• Pulsed laser deposition to grow In2O3 films with varying crystallinity.
• Grazing angle X-ray diffraction (GIXRD) for structural analysis.
• Hall transport measurements for electrical properties.
• High-resolution transmission electron microscopy (HRTEM) and electron diffraction for microstructure.
• Extended X-ray absorption fine structure (EXAFS) and ab initio molecular dynamics (MD) simulations for atomic structure.

Main Results:

• A model of amorphous In2O3 as a network of InO6 polyhedra was developed, validated by EXAFS and MD simulations.
• Mechanisms governing transport properties were identified for crystalline, amorphous-to-crystalline, and amorphous In2O3.
• A distinct correlation between film structure and observed transport properties was highlighted.

Conclusions:

• The study provides a comprehensive understanding of In2O3 thin film formation and properties.
• The proposed amorphous structure model offers insights into the behavior of disordered indium oxide.
• The identified structure-property relationships are key for optimizing In2O3-based electronic devices.