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The introduction of magnetism in two-dimensional (2D) materials represents an intense field of research nowadays and the quest to reach above-room-temperature ordering temperatures is still underway. Intrinsic ferromagnetism was discovered in 2017 in CrI$_{{3}}$ and Cr$_{{2}}$Ge$_{{2}}$Te$_{{6}}$ in the monolayer form with low Curie temperatures. An alternative method to introduce magnetism into conventional 2D materials is substitutional doping with magnetic impurities similarly to three-dimensional diluted magnetic semiconductors. The case of Mn-doped transition metal dichalcogenide (MoS$_{{2}}$, MoSe$_{{2}}$, WS$_{{2}}$, WSe$_{{2}}$) monolayers is very interesting because combining out-of-plane ferromagnetism and valley contrast leads to ferrovalley materials. In this work, we focus on the incorporation of Mn in MoSe$_{{2}}$ by molecular beam epitaxy on graphene which has been rarely addressed up to now. By using a multiscale characterization approach, we demonstrate that Mn atoms are incorporated into the MoSe$_{{2}}$ monolayer up to 5 atomic percent. However, when incorporated into the film, Mn atoms tend to diffuse to the grain edges forming undefined Mo$_{{{\it x}}}$Mn$_{{{\it y}}}$Se$_{{{\it z}}}$ phase at grain boundaries after completion of the MoSe$_{{2}}$ monolayer. This segregation leaves the crystalline and electronic structure of MoSe$_{{2}}$ unmodified. Above 5%, the saturation of Mn content in MoSe$_{{2}}$ leads to the formation of epitaxial MnSe clusters.

X‐ray photoelectron spectroscopy (XPS) provides quantitative information from photoemission peaks and shapes observed within the background due to the inelastic scattering of photoelectrons. To quantify the signal, both photoemission peaks and background in spectra must be adjusted for instrumental transmission variations that are a consequence of changes in efficiency when recording electrons with different kinetic energy. While it is generally assumed that correcting spectroscopic data for transmission is a necessary part of quantification by XPS, there are consequences for the quantification of spectra measured using an instrument for which transmission has significant curvature. In this Insight, the implications of curvature in transmission characteristics are discussed and a method based on XPS microscopy is proposed that ensures the transmission response of an instrument is free from significant curvature. An example of an instrument for which a flat transmission response is presented is achieved through collecting spectra using lens modes designed to measure stigmatic images. [ABSTRACT FROM AUTHOR]

Monochromatic Cr Kα radiation (5414.8 eV) was used to acquire high-energy photoelectron spectroscopy (HAXPES) data on pure Mo and bulk MoSe2 compound with special attention paid to binding energy scale correction and quantification. The reported spectra include a survey scan and high-resolution Mo 2s, Mo 2p1/2, Mo 2p3/2, Mo 3d, Mo 3p1/2, Mo 3p3/2, Mo 3s, Mo 4s, Mo4p, Se2s, Se 2p1/2, Se 2p3/2, Se 3s, Se 3p1/2, Se 3p3/2, and Se 3d core-levels. The data will be useful as reference core-level spectra for HAXPES studies on molybdenum and its compounds. [ABSTRACT FROM AUTHOR]

With the development in the early 2000s of new cluster ion sputtering sources, a reliable analysis of organic multilayers and interfaces has become possible. Nowadays, time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) and X‐ray photoelectron spectroscopy (XPS) depth profiling are routinely used to investigate organic stacks. However, analysis beams can cause bond scission or beam‐induced degradations that accumulate in buried layers. We developed a correlative protocol that minimises damages related to analysis beams. It uses a shallow angle bevel crater fabricated inside the ToF‐SIMS analysis chamber. With this preparation method, the in‐depth information is displayed over the surface of the bevel crater. XPS profiles and high‐resolution spectra paired with ToF‐SIMS images enable an easy identification of the organic layers and complete understanding of their chemistry. The reduction of beam‐induced degradation is achieved by minimising the acquisition times, therefore beam exposure on materials. Finally, an important advantage of this preparation method is that the analysis can be performed on exactly the same spot by multiple techniques. Several ToF‐SIMS and XPS acquisitions can be carried out with various parameters (investigation of backscattered Arn+ cluster ion fragments, tandem MS imaging...) as well as analysis with other techniques that possess limitations in spatial resolution and/or inaptitude to probe buried layers such as Raman or AFM. [ABSTRACT FROM AUTHOR]

Monochromatic Cr Kα radiation (5414.8 eV) was used to acquire high-energy photoelectron spectroscopy data on pure W and bulk WSe2 compound. The reported spectra include a survey scan and high-resolution W 3p1/2, W 3p3/2, W 3d3/2, W 3d5/2, W 4s, W 4p1/2, W 4p3/2, W 4d, W 4f, Se 2s, Se 2p1/2, Se 2p3/2, Se 3s, and Se 3p core-levels. The data will be useful as reference core-level spectra for HAXPES studies on tungsten and its compounds. [ABSTRACT FROM AUTHOR]

Transition metal oxides are promising candidates in the development of valence change memories thanks to their ability to present the valence change mechanism. The resistive switching mechanism of TiN/LaMnO3 + δ (LMO)/Pt devices was investigated by operando hard X-ray photoelectron spectroscopy after careful in situ electrical characterization. The results presented here highlight the oxygen exchange process at the TiN/LMO interface. The active TiN top electrode acts as an oxygen getter, pumping O2− anions that are attracted by the positive bias and repelling them under negative bias. This drift of charged defects is correlated with variations of the interfacial resistance. Our results confirm the critical role of the TiN/LMO interface and oxygen drift in the resistive switching behavior of such devices. [ABSTRACT FROM AUTHOR]

We present a study of the impact of Pb excess content on electrical performance of lead zirconate titanate (PbZr0.52Ti0.48O3, PZT) thin-film capacitors. High Pb excess eliminates the ZrOx interface layer between the PZT and the electrode but also reduces the breakdown field, while the linear dielectric character of the capacitor response increases with Pb excess. The chemical sensitivity of hard x-ray photoelectron spectroscopy with in situ bias provides direct evidence of a polar but the non-ferroelectric PbOx phase in the bulk of the sol-gel film. The phase has a distinct core level signature and is consistent with the dielectric response at low field, which becomes more ferroelectric at higher field, as well as the lower remanent polarization and breakdown field. [ABSTRACT FROM AUTHOR]

A study to describe an extensive experimental research of TiN/HfO(sub 2)/SiGE and TiN/HfO(sub 2)/Si cap/SiGE gate stacked-transistors is conducted. The results reveal that due to the interface optimization, Si(sub 0.72)Ge(sub 0.28) pMOSFETs exhibit a 58% higher mobility at effective field than the universal SiO(sub 2)/Si reference and a 90% higher mobility than the HfO(sub 2)/Si reference.

Si (100) wafer was analyzed by high-energy photoelectron spectroscopy (HAXPES) using monochromatic Cr Kα radiation (5414.8 eV). The HAXPES spectra reported here include a survey scan and high-resolution spectra of Si 1s, Si 2s, and Si 2p core-levels. [ABSTRACT FROM AUTHOR]

A thick alumina sample was analyzed by hard x-ray photoelectron spectroscopy by means of a lab-scale spectrometer equipped with a Cr Kα (5414.8 eV) excitation source. The reported spectra include a survey scan as well as Al 1s, Al 2s, Al 2p, O 1s, and C 1s core-level spectra. [ABSTRACT FROM AUTHOR]