Characterization of amorphous In2O3: An ab initio molecular dynamics study

Abstract

In this work, we report on the structural and electronic properties of amorphous In2O3 obtained with ab initio molecular dynamics. Our results show crystal-like short range InO6 polyhedra having average In-O distance consistent with x-ray spectroscopy data. Structural disorder yields band tailing and localized states, which are responsible of a strong reduction of the electronic gap. Most importantly, the appearance of a peculiar O–O bond imparts n-type character to the amorphous compound and provides contribution for interpreting spectroscopic measurements on indium based oxidized systems. Our findings portray characteristic features to attribute transparent semiconductive properties to amorphous In2O3.

In Situ Hall Effect Monitoring of Vacuum Annealing of In2O3:H Thin Films

“…Due to the disorder in the amorphous phase, optical transitions that are usually parity forbidden in cubic In 2 O 3 [18] could occur and lead to an optical band gap similar to the fundamental gap. A reduced band gap for a-In 2 O 3 is also predicted by theory [19,20]. …”

Universal Medium-Range Order of Amorphous Metal Oxides

“…For comparison, we also generated a-SiO 2 (Si 108 O 216 , 2:14 g=cm 3 ). Our computer models agree on the short-range order with previous experimental and ab initio studies [14,16,17,[19][20][21][22][23]31] (see the Supplemental Material [28] for details). As an example of the DRPS structure, we generated the amorphous solid consisting of 108 particles interacting through Lennard-Jones (LJ) potential for argon [4].…”

“…However, as far as the short-range order, which is involved with the arrangement of nearestneighbor atoms, is concerned, the atomic structure strongly depends on the material. For example, four-and fivefoldcoordinated Al atoms predominate in a-Al 2 O 3; [16,17], sixfold-coordinated Ti (In) atoms predominate in a-TiO 2 (a-In 2 O 3 ) [14,[18][19][20], six-and sevenfold-coordinated Zr (Hf) atoms predominate in a-ZrO 2 (a-HfO 2 ) [21][22][23].…”

Dual-Random-Sphere-Packing Structure of Liquid and Amorphous Li₂O

“…The short-range order, namely order in the nearest-neighbor Li-O pairs, is characterized by the coordination number distribution. Although the short-range order is not our main subject, we study the coordination number distributions of l-and a-Li2O, since those are often discussed in literature on AMOs [17][18][19][20][21][22][23][24][25]. The Li-O partial radial distribution function (PRDF) is shown in Fig.…”