Low-Energy Ar⁺ Ion-Beam-Induced Amorphization and Chemical Modification of Potassium Titanyl Arsenate (001) Crystal Surfaces

Abstract

The effect of 1.5 keV Ar+ ion irradiation on the (001) surfaces of potassium titanyl arsenate, KTiOAsO4 (KTA), has been investigated using reflection high-energy electron diffraction (RHEED) and X-ray photoelectron spectroscopy (XPS). The (001) KTA surface is very sensitive to 1.5 keV Ar+ ion irradiation which induces significant structural modification in the top surface layers. The <As−O> bonds in the KTA crystal lattice are relatively less unstable when compared to <Ti−O>; reduction of As5+ ions with the formation of As0 and partial As loss from the top surface occurs with Ar+ ion irradiation. The formation of an unstable layer with chemically active and passive arsenic states may be a factor reducing the optical parameters and durability of nonlinear devices involving KTA.

Structural and chemical properties of highly oriented cadmium sulfide (CdS) cauliflower films

“…However, the difference is not so pronounced, and more sensitive parameters are necessary to quantify the effect in sulfides. Such approach resulted in accurate interpretation of the chemical analysis of oxide and sulfide crystal surfaces [25][26][27][28]. In the present case, therefore, the energy difference between the Cd metal core-level and S 2p level, i.e., D(Cd 3d 5/2 -S 2p 3/2 ), can be used as a parameter for chemical bonding characterization.…”

Electronic structure of KTiOAsO4: A comparative study by the full potential linearized augmented plane wave method, X-ray emission spectroscopy and X-ray photoelectron spectroscopy

“…At the finishing stage of polishing, the nanodiamond powder, 0.1 grade, lubricated by water was applied. The RHEED patterns [21] have revealed the system of wide monocrystal streaks for the (0 0 1) surface of the KTA sample under investigation.…”

“…In previous papers [21,22] we have reported results of measurements of binding energies of core-level electrons for a KTA crystal as well as the influence of 1.5 keV Ar + ion bombardment on the X-ray photoelectron core-level spectra peculiarities and reflection highenergy electron diffraction (RHEED) patterns derived for the (0 0 1) surface of KTA. The both X-ray photoelectron spectroscopy (XPS) and RHEED methods have rendered [21,22] a high sensitivity of the (0 0 1)KTA surface to the Ar + ion bombardment: the long-range order of the KTA surface is lost during irradiation, leading to the formation of completely amorphous surface layers at an ion dose of 2.1 × 10 16 ions/cm 2 .…”

“…The both X-ray photoelectron spectroscopy (XPS) and RHEED methods have rendered [21,22] a high sensitivity of the (0 0 1)KTA surface to the Ar + ion bombardment: the long-range order of the KTA surface is lost during irradiation, leading to the formation of completely amorphous surface layers at an ion dose of 2.1 × 10 16 ions/cm 2 . Additionally, it has been established that the As-O bonds in KTA are relatively less stable and are very sensitive to the Ar + ion bombardment [21]. The formation of unstable layers with chemically active and passive arsenic states observed for the (0 0 1)KTA surface [21] was supposed to be a factor reducing the optical parameters and durability of nonlinear devices involving potassium titanyl arsenate.…”

“…Additionally, it has been established that the As-O bonds in KTA are relatively less stable and are very sensitive to the Ar + ion bombardment [21]. The formation of unstable layers with chemically active and passive arsenic states observed for the (0 0 1)KTA surface [21] was supposed to be a factor reducing the optical parameters and durability of nonlinear devices involving potassium titanyl arsenate.…”