scispace - formally typeset
Search or ask a question
Topic

Photoemission spectroscopy

About: Photoemission spectroscopy is a research topic. Over the lifetime, 10821 publications have been published within this topic receiving 250888 citations. The topic is also known as: photoelectron spectroscopy & PES.


Papers
More filters
Journal ArticleDOI
TL;DR: In this article, a Corundum-structured iridium oxide (α-Ir2O3), showing p-type conductivity, is a strong candidate to form high-quality pn heterojunctions with α-Ga 2O3.
Abstract: Corundum-structured iridium oxide (α-Ir2O3), showing p-type conductivity, is a strong candidate to form high-quality pn heterojunctions with α-Ga2O3. We fabricated α-Ir2O3/α-Ga2O3 pn heterojunction diodes and they showed well-defined rectifying current-voltage (I-V) characteristics with the turn-on voltage of about 2.0 V. The band alignment at the α-Ir2O3/α-Ga2O3 interface was investigated by X-ray photoemission spectroscopy, revealing a staggered-gap (type-II) with the valence- and conduction-band offsets of 3.34 eV and 1.04 eV, respectively. The total barrier height for electrons was about 2.4 eV, which reasonably agreed with the turn-on voltage in the I-V characteristics. This means that electrons are mainly attributed to electrical conduction around the turn-on voltage.Corundum-structured iridium oxide (α-Ir2O3), showing p-type conductivity, is a strong candidate to form high-quality pn heterojunctions with α-Ga2O3. We fabricated α-Ir2O3/α-Ga2O3 pn heterojunction diodes and they showed well-defined rectifying current-voltage (I-V) characteristics with the turn-on voltage of about 2.0 V. The band alignment at the α-Ir2O3/α-Ga2O3 interface was investigated by X-ray photoemission spectroscopy, revealing a staggered-gap (type-II) with the valence- and conduction-band offsets of 3.34 eV and 1.04 eV, respectively. The total barrier height for electrons was about 2.4 eV, which reasonably agreed with the turn-on voltage in the I-V characteristics. This means that electrons are mainly attributed to electrical conduction around the turn-on voltage.

71 citations

Journal ArticleDOI
TL;DR: In this article, the effects of bulklike and surfacelike surroundings on the electronic density of states of a variety of Si-H bonding conformations in hydrogenated amorphous silicon are examined using the cluster Bethe-lattice approach.
Abstract: The effects of bulklike and surfacelike surroundings on the electronic density of states of a variety of Si-H bonding conformations in hydrogenated amorphous silicon are examined using the cluster Bethe-lattice approach. Firstly, we discover that two fundamentally different bonding patterns, with different consequences for the doping mechanism, are consistent with ultraviolet photoemission spectroscopy (UPS) data. These are (1) H atoms bonded in microcrystalline regions and (2) clusters of monohydrides (SiH) in a continuous random network. Our results suggest an experiment in which x-ray photoemission spectroscopy and UPS taken together should distinguish between (1) and (2) and hence contribute toward understanding doping. Secondly, by using the calculated densities of states, the energies of a number of conformations and dehydrogenation reactions are calculated with the use of an empirical bond-strength total-energy scheme. Our results agree with results from annealing experiments. We introduce an improvement in the Bethe-lattice method which permits efficient solution of a second-neighbor tight-binding Hamiltonian, and which is valid for $N\mathrm{th}$-neighbor interactions. We also estimate the Hubbard $U$, Stokes shifts, and electronic states associated with neutral and charged dangling bonds.

71 citations

Journal ArticleDOI
TL;DR: In this paper, the interaction of water and carbon dioxide with nanostructured epitaxial (Ba,Sr)TiO3(001) thin film and bulk single crystal Sr TiO3 (001) surfaces was studied using x-ray photoemission spectroscopy (XPS), thermal desorption (TDS), and density functional theory (DFT) and showed that defect surface sites are important for the observed strong adsorbate surface reactivity.
Abstract: The interaction of water and carbon dioxide with nanostructured epitaxial (Ba,Sr)TiO3(001) thin film and bulk single crystal SrTiO3(001) surfaces was studied using x-ray photoemission spectroscopy (XPS), thermal desorption spectroscopy (TDS), and density functional theory (DFT). On both surfaces, XPS and TDS indicate D2O and CO2 chemisorb at room temperature with broad thermal desorption peaks (423–723 K) and a peak desorption temperature near 573 K. A comparison of thermal desorption Redhead activation energies to adsorption energies calculated using DFT indicates that defect surface sites are important for the observed strong adsorbate-surface reactivity. Numerical calculations of the competetive adsorption/desorption equilibria for H2O and CO2 on SrTiO3(001) surfaces show that for typical atmospheric concentrations of 0.038% carbon dioxide and 0.247% water vapor the surfaces are covered to a large extent with both adsorbates. The high desorption temperature indicates that these adsorbates have the pote...

71 citations

Journal ArticleDOI
TL;DR: An approach for controlling the layer thickness and crystallographic stacking sequence of multilayer graphene films at the wafer scale via Cu–Si alloy formation using direct chemical vapour deposition is proposed.
Abstract: Multilayer graphene and its stacking order provide both fundamentally intriguing properties and technological engineering applications. Several approaches to control the stacking order have been demonstrated, but a method of precisely controlling the number of layers with desired stacking sequences is still lacking. Here, we propose an approach for controlling the layer thickness and crystallographic stacking sequence of multilayer graphene films at the wafer scale via Cu-Si alloy formation using direct chemical vapour deposition. C atoms are introduced by tuning the ultra-low-limit CH4 concentration to form a SiC layer, reaching one to four graphene layers at the wafer scale after Si sublimation. The crystallographic structure of single-crystalline or uniformly oriented bilayer (AB), trilayer (ABA) and tetralayer (ABCA) graphene are determined via nano-angle-resolved photoemission spectroscopy, which agrees with theoretical calculations, Raman spectroscopy and transport measurements. The present study takes a step towards the layer-controlled growth of graphite and other two-dimensional materials.

70 citations


Network Information
Related Topics (5)
Band gap
86.8K papers, 2.2M citations
92% related
Thin film
275.5K papers, 4.5M citations
90% related
Raman spectroscopy
122.6K papers, 2.8M citations
89% related
Amorphous solid
117K papers, 2.2M citations
88% related
Silicon
196K papers, 3M citations
87% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023128
2022262
2021227
2020281
2019247
2018263