Enabling p-type doping in In2O3 by a band engineering through alloying

ORAL

Abstract

In2O3 is a wide-band gap semiconductor of great importance to the optoelectronic industry. It is often used as transparent contact for solar cells, LEDs, and liquid crystal displays. It has a highly dispersive conduction band, composed of the In s orbitals, that lie relatively low with respect to the vacuum level, making it easy to dope n-type, while the low-energy valence band, composed mostly of O p orbitals, making it difficult to achieve p-type doping because acceptor impurities introduce deep levels in the gap. One way to overcome this limitation is to raise its valence band. Using first-principles calculations we explore different approaches to lift the valence band in In2O3 by alloying. We discuss different alloying elements, both on oxygen and metal sites. We compute the formation enthalpy of these alloys, and their stability with respect to phase separation. We calculate band gaps, and analyze the effects of alloying on the position of the valence and conduction bands, determining the band alignment between the alloys and the parent compounds. Finally, we address their optical properties by calculating absorption coefficients as a function of alloy composition.

–

Presenters

  • Fernando Sabino

    Department of Material science and Engineering, University of Delaware, Department of Physics & Astronomy, University of Delaware, Materials Science and Engineering, University of Delaware

Authors

  • Fernando Sabino

    Department of Material science and Engineering, University of Delaware, Department of Physics & Astronomy, University of Delaware, Materials Science and Engineering, University of Delaware

  • Suhuai Wei

    Beijing Computational Science Research Center

  • Anderson Janotti

    Department of Material science and Engineering, University of Delaware, Department of Physics & Astronomy, University of Delaware, Materials Science and Engineering, University of Delaware, University of Delaware, Department of Materials Science & Engineering, University of Delaware, Department of Materials Science and Engineering, University of Delaware