Theoretical Study of Oxygen-Vacancy Distribution in In₂O₃

Abstract

In2O3 is of particular interest as a wide-gap transparent semiconductor oxide, in which the shallow donor defect of the oxygen vacancy plays an important role in electronic properties. Herein, we focus on the oxygen vacancy with various concentrations in In2O3, where the distribution is found to be crucial to the structural stabilities. For a specific supercell, the formation energies of oxygen-vacancy pairs remarkably depend on the distance between the two vacancies, which can be used to determine the oxygen-vacancy distribution in the nonstoichiometric In2O3 structure. Interestingly, when two oxygen vacancies share a same In atom, the structures are approximately stabilized with the decreasing of distance. However, when two oxygen vacancies are not attached to the same In atom, the structures become more stable with the increasing of distance between vacancies. In addition, the gap states induced by oxygen vacancies move toward the valence band maximum (VBM) when the nearest distance between the two vacancies decreases, which will have a great effect on the conductivity.

Oxygen relocation during HfO2 ALD on InAs

“…Since the oxide thicknesses in our study vary strongly between the thermal and native oxide samples, we now consider the details of the oxygen transfer separately for the two types of oxides. Assuming that a monolayer of the oxide has a thickness of around 5 Å, estimated by an average of In 2 O and As 3 O 5 oxide 43,44 , this translates into surface coverages of 22%, 28%, 42% and 46%. Since the XP spectra were collected in several spots of the sample and no differences between the different spots were detected, we conclude that the oxide islands are significantly smaller than the size of the beam spot on the Please do not adjust margins Please do not adjust margins sample (100 × 100 µm 2 ) and that they are distributed homogeneously on the sample surface.…”

Room-Temperature Postannealing Reduction via Aqueous Sodium Borohydride and Composition Optimization of Fully Solution-Processed Indium Tin Oxide Films

“…Previous reports have postulated that oxygen vacancies may contribute to increased charge carrier generation in n-type transparent conductive oxides ,,, and this effect is inversely proportional to the partial pressure of oxygen . Hou et al calculate that the most energetically favorable n-type intrinsic defect is oxygen loss, where the resulting loss of an anion is then charge-compensated by additional electrons .…”

“…However, when 3 M LAH was tested in place of 3 M NaBH 4 , the electrical qualities were poorer but still improved over the traditional fuel-based H 2 -furnace process [R s = 121 Ω/□, N b = 1.61 × 10 20 #/cm 3 , σ = 612 Ω −1 cm −1 , μ = 6.43 cm 2 /(V s)], indicating that the electrochemical reduction of ITO is an important component. Previous reports have postulated that oxygen vacancies may contribute to increased charge carrier generation in n-type transparent conductive oxides 21,43,46,47 and this effect is inversely proportional to the partial pressure of oxygen. 48 Hou et al calculate that the most energetically favorable n-type intrinsic defect is oxygen loss, where the resulting loss of an anion is then charge-compensated by additional electrons.…”

Study on the electronic properties of In2O3 doped with Eu3+: A First Principle Calculation

“…During the preparation of In 2 O 3 , due to the limitation of preparation conditions, oxygen vacancies (V O ) are easily formed spontaneously. As a shallow donor, it can provide additional electrons and more active sites, enhance conductivity, and form a wider electron depletion layer on the surface, providing more electron exchange channels [1]. In the application of gas sensors, the rich V O provide more active sites, thus improving the gas sensing properties of materials and achieving ultra-fast response speed.…”

“…3+ doped In 2 O 3 in O-poor (In-rich) and O-rich (In-poor) condition and temperature at with the chemical potential of O was shown in eq (2)[1].…”