Unusual oxidation-induced core-level shifts at the HfO2/InP interface

Abstract

X-ray photoelectron spectroscopy (XPS) is one of the most used methods in a diverse field of materials science and engineering. The elemental core-level binding energies (BE) and core-level shifts (CLS) are determined and interpreted in the XPS. Oxidation is commonly considered to increase the BE of the core electrons of metal and semiconductor elements (i.e., positive BE shift due to O bonds), because valence electron charge density moves toward electronegative O atoms in the intuitive charge-transfer model. Here we demonstrate that this BE hypothesis is not generally valid by presenting XPS spectra and a consistent model of atomic processes occurring at HfO2/InP interface including negative In CLSs. It is shown theoretically for abrupt HfO2/InP model structures that there is no correlation between the In CLSs and the number of oxygen neighbors. However, the P CLSs can be estimated using the number of close O neighbors. First native oxide model interfaces for III-V semiconductors are introduced. The results obtained from ab initio calculations and synchrotron XPS measurements emphasize the importance of complementary analyses in various academic and industrial investigations where CLSs are at the heart of advancing knowledge.

XPS and HAXPES analyses for pre-sputtered InP surface and InP/Pt interface

“…The two components at 444.4 and 445.3 eV are assigned as the bondings of In-P and In-O, respectively. [22][23][24][25][26][27][28] These results demonstrate that more indium atoms on the surface of #1b were oxidized than #1a. The P 2p XP spectra also deconvoluted into two components assigned as P-In and P-O bondings.…”

“…As there was no report about P 1s spectra from InP materials, it was attempted to presume the origins of the two sub peaks recognized in the P 1s spectra, considering from the XPS studies about P 2p. [22][23][24][25][26][27][28] As shown in Fig. 3, the chemical shifts of the sub peaks from the P-In main peak were approximately 5.5 and 1.6 eV.…”

“…The P 2p XP spectra also deconvoluted into two components assigned as P-In and P-O bondings. [22][23][24][25][26][27][28] Note that both the P 2p 3/2 and P 2p 1/2 orbitals appear with a certain energy separation in each peak. It was also confirmed that the P-O/P-In peak area ratio of #1b was obviously larger than that of #1a.…”

RuFe Alloy Nanoparticle-Supported Mesoporous Carbon: Efficient Bifunctional Catalyst for Li-O2 and Zn–Air Batteries

“…The sharing of the elements with their neighbor atoms in the bond arrangement can cause a shift in the core-level binding energy. 35 The binding energy values at 398.4, 399.9, and 401 eV are attributed to pyridinic-N, pyrrolic-N, and graphitic-N species, respectively. 36 It revealed that all samples contained relatively large amounts of graphitic-N species, especially Fe@NC-900(5h) contained a little higher pyridinic species (Figure 2c).…”

Модификация Атомной И Электронной Структуры Поверхности Полупроводников А-=sup=-Iii-=/Sup=-В-=sup=-v-=/Sup=- На Границе С Растворами Электролитов О Б З Ор

“…3). Слой естественного окисла на поверхности InP(100) содержит оксиды In 2 O, а также фосфаты, InPO 4 , и гидрофосфаты, In x (HPO 4 ) y , индия [82,83,86].…”