Design and Realization of Ohmic and Schottky Interfaces for Oxide Electronics

Area of Science:

• Materials Science
• Condensed Matter Physics
• Solid-State Chemistry

Background:

• Understanding charge transfer at complex oxide interfaces is crucial for device functionality.
• Existing models for simple semiconductors are insufficient for ABO3 perovskites.
• Tailoring oxide interfaces requires precise control over band alignment.

Purpose of the Study:

• To design and experimentally validate Ohmic and Schottky-like charge transfer mechanisms at oxide/oxide semiconductor/metal interfaces.
• To develop a predictive method for band alignment and charge transfer in ABO3 perovskites.
• To explore the interface properties of SrBO3 (B=V-Ta) with SrTiO3.

Main Methods:

• Utilized a novel method for predicting band alignment and charge transfer in ABO3 perovskites.
• Experimentally validated Ohmic and Schottky-like charge transfer designs.
• Investigated interfaces between SrTiO3 and SrBO3 (B=V, Nb, Ta).

Main Results:

• Confirmed charge accumulation in SrTiO3 for Nb and Ta interfaces, forming high-mobility metallic Ohmic contacts.
• Demonstrated no charge transfer for V interfaces, resulting in a highly conductive epitaxial gate metal.
• Validated a predictive method applicable to ABO3 perovskites where simple semiconductor rules fail.

Conclusions:

• The developed method accurately predicts band alignment and charge transfer in complex oxide systems.
• Ohmic and Schottky-like contacts were successfully engineered at oxide interfaces.
• This work facilitates the integration of ABO3 perovskites into practical electronic devices.