相关论文: Negative oxygen vacancies in HfO$_2$ as charge tra…

In this study, we demonstrated experimentally and theoretically that oxygen vacancies are responsible for the charge transport in HfO$_2$. Basing on the model of phonon-assisted tunneling between traps, and assuming that the electron traps…

We perform ab initio calculations, based on density functional theory, of substitutional and vacancy defects in the monoclinic hafnium oxide (m-HfO2) and alpha-quartz (SiO2). The neutral oxygen vacancies and substitutional Si and Hf defects…

We find that O-vacancy (Vo) acts as a hole trap and play a role in negative bias illumination stress instability in amorphous In-Ga-Zn-O thin film transistors. Photo-excited holes drifted toward the channel/dielectric interface due to small…

Cubic hafnia (HfO$_2$) is of great interest for a number of applications in electronics because of its high dielectric constant. However, common defects in such applications degrade the properties of hafina. We have investigated the…

We have determined the electronic and atomic structure of N doped TiO2 using a combination of hard x-ray photoelectron spectroscopy (HAXPES) and first- principles density functional theory calculations. Our results reveal that N doping of…

Defects such as oxygen vacancy are widely considered to be critical for the performance of HfO2-based devices, and yet atomistic mechanisms underlying various exotic effects such as wake-up and fluid imprint remain elusive. Here, guided by…

We investigated the unoccupied part of the electronic structure of the oxygen-deficient hafnium oxide (HfO$_{\sim1.8}$) using soft x-ray absorption spectroscopy at O $K$ and Hf $N_3$ edges. Band-tail states beneath the unoccupied Hf 5$d$…

We perform full-potential screened-hybrid density-functional theory (DFT) calculations to compare the thermodynamic stability of neutral and charged states of the surface oxygen vacancy at the rutile TiO$_2$(110) surface. Solid-state…

The charge transport mechanism of electron via traps in amorphous SiO$_2$ has been studied. Electron transport is limited by phonon-assisted tunneling between traps. Thermal and optical trap energies $W_\mathrm{t}=1.6$ eV,…

{\it Ab initio} calculations within density functional theory with generalized gradient approximation have been performed to study the effects of oxygen vacancies on the electronic structure and magnetism in undoped V$_2$O$_{5-x}$ ($0 < x <…

Hexagonal boron nitride (hBN) hosts luminescent defects possessing spin qualities compatible with quantum sensing protocols at room temperature. Vacancies, in particular, are readily obtained via exposure to high-energy ion beams. While the…

MOSFETs based on wide band-gap semiconductors are suitable for operations at high temperature, at which additional atomic-scale processes that are benign at lower temperatures can get activated which results in device degradation. Recently…

The discovery of ferroelectric HfO2 in thin films and more recently in bulk is an important breakthrough because of its silicon-compatibility and unexpectedly persistent polarization at low dimensions, but the origin of its ferroelectricity…

We demonstrate a thermodynamic formulation to quantify defect formation energetics in an insulator under high electric field. As a model system, we analyzed neutral oxygen vacancies (color centers) in alkaline-earth-metal binary oxides…

Fourier transform deep level transient spectroscopy has been performed between 80 K and 550 K in five n-type ZnO samples grown by different techniques. The capture cross section and ionization energy of four electron traps have been deduced…

We perform first-principles calculations of the quasiparticle defect states, charge transition levels, and formation energies of oxygen vacancies in rutile titanium dioxide. The calculations are done within the recently developed combined…

In this study, we demonstrated experimentally and theoretically that the charge transport mechanism in amorphous Hf$_{0.5}$Zr$_{0.5}$O$_2$ is phonon-assisted tunneling between traps like in HfO$_2$ and ZrO$_2$. The thermal trap energy of…

Cu$_2$O has appealing properties as an electrode for photo-electrochemical water splitting, yet its practical performance is severely limited by inefficient charge extraction at the interface. Using hybrid DFT calculations, we investigate…

We characterise an efficient optically-heated neutral atom source for ion trapping. We observe loading rates of up to $24(3)\,\mathrm{s}^{-1}$ with heating powers below $85\,\mathrm{mW}$, and demonstrate loading of a single ion in under…

This work explores the Zn vacancy in ZnO using hybrid density functional theory calculations. The Zn vacancy is predicted to be an exceedingly deep polaronic acceptor that can bind a localized hole on each of the four nearest-neighbor O…