XPS Investigation of the Oxidation States of the As-Deposited Ta Films Prepared by Magnetron Sputtering Technology

Abstract

Due to their versatile and unique properties, tantalum-based thin films have been extensively studied. However, tantalum is susceptible to oxidation due to its higher chemical activity, which is crucial regardless of whether oxidations of Ta are beneficial or detrimental. Therefore, the oxidation of Ta during material processing, especially without conscious means, should be taken seriously. In this study, pure Ta films were fabricated by magnetron sputtering under set procedure parameters. The effects of base pressure and substrate temperature on the degree of oxidation of Ta films were investigated. The results revealed that the magnitude of the base pressure directly affects the oxidation state of the as-deposited Ta films. When preferably avoiding the oxidation of sputtered Ta films, the base pressure should be controlled below 4.4 × 10−4 Pa. The substrate temperature has little effect on the oxidation state of the as-deposited Ta films under a base pressure ranging from about 10−2 Pa to 10−4. We hope that this study can provide some references for controlling the oxidation states of Ta involved in relevant film preparation.

Performance Enhancement of the Li6PS5Cl‐Based Solid‐State Batteries by Scavenging Lithium Dendrites with LaCl3‐Based Electrolyte

“…The XPS spectrum of Ta 4f for the pristine LTLC ( Figure a) shows one set of doublet peaks at 28.7 and 26.7 eV (blue), which belong to the 4f 5/2 and 4f 7/2 components of Ta 5+ , respectively. [ 15 ] In contrast, after cycling (Figure 6b), one additional set of doublet peaks appear at 24.4 and 22.4 eV (red), which can be assigned to Ta 0 . When etching off 10 nm of the top surface with Ar + ‐ions bombardment, another set of doublet peaks at 26.2 and 24.2 eV (red) emerge (Figure 6c), which are believed to come from the etching‐caused partial reduction of Ta 5+ (denoted as Ta n+ ) according to literature.…”

Activating Angiogenesis and Immunoregulation to Propel Bone Regeneration via Deferoxamine-Laden Mg-Mediated Tantalum Oxide Nanoplatform

“…Furthermore, the chemical states of DFO-Mg-TaO were analyzed by the respective highresolution spectra; the peaks in Ta 4f (Figure 1g) located in 25.72 and 23.80 eV can be indexed to Ta 4f 5/2 and Ta 4f 7/2 , respectively, and the peak spacing of 1.92 eV between them is further evidence of the presence of tantalum in the form of Ta 2 O 5 . 33 In the O 1s high-solution spectrum (Figure 1h), the peaks located at 529.12 and 527.95 eV can be indexed to oxygen in adsorbed water and oxygen in tantalum−oxygen bonds, respectively. The peak of the Mg ion is found in the Mg 1s spectrum (Figure 1i).…”