The Effect of Deposition Parameters on the Structure and Mechanical Properties of Chromium Oxide Coatings Deposited by Reactive Magnetron Sputtering

Abstract

Appropriate conditions for depositing hard Cr 2 O 3 coatings by reactive sputtering techniques have yet to be defined. To fill this gap, the effect of principal deposition parameters, including deposition pressure, temperature, Cr-target voltage, and Ar/O 2 ratio, on both the structure and mechanical properties of chromium oxide coatings was investigated. A relationship between processing, structure, and the mechanical properties of chromium oxide coatings was established. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, and X-ray Photoelectron Spectroscopy (XPS) were used to characterize the morphology, structure, and chemical compositions of the coatings that were prepared. An optical profilometer was employed to measure both the roughness and thickness of the coatings. The hardness and Young's modulus of the coatings both as-deposited and after annealing conditions were measured by nanoindentation. The results showed that depositing hard Cr 2 O 3 coatings is a highly critical task, requiring special deposition conditions. Cr 2 O 3 coatings with a high hardness of approximately 25 GPa could be achieved at room temperature, at a low pressure of 1.6 × 10 −1 Pa, where Cr-target voltage and oxygen content were 260 V and between 15-25 vol % of total gas, respectively. A dense stoichiometric Cr 2 O 3 structure was found to be responsible for the high chromium oxide coating hardness observed.

Structural Changes Induced by Heating in Sputtered NiO and Cr2O3 Thin Films as p-Type Transparent Conductive Electrodes

“…A decrease of the 1LO phonon energy was related to VNi defec with the tensile lattice distortion detected by XRD in the as-grown chromium oxide layers, Raman shifts were assigned to the A1g and [37]. The signal increment observed at ~650 cm −1 for the as-grown s tributed to the forbidden Raman modes of Cr2O3 activated in am [26,38], which was in accordance with the absence of diffraction sponding XRD pattern (Figure 1). Otherwise, the Raman band that ap after heating was related to the Cr(VI) states in CrO3 [39] or Cr2O5 [40 °C heated sample, the small signal increment around 850 cm −1 was phase detected by XRD, which decomposed into Cr2O3 and CrO3 dur °C.…”

“…For the chromium oxide layers, Raman shifts were assigned to the A 1g and E g modes of Cr 2 O 3 [37]. The signal increment observed at 650 cm −1 for the as-grown sample could be attributed to the forbidden Raman modes of Cr 2 O 3 activated in amorphous materials [26,38], which was in accordance with the absence of diffraction peaks in the corresponding XRD pattern (Figure 1). Otherwise, the Raman band that appeared at~850 cm −1 after heating was related to the Cr(VI) states in CrO 3 [39] or Cr 2 O 5 [40] forms.…”

“…During heating in air at 300 • C or 500 • C, NiO crystallites enlarged slightly to 45 nm while the lattice constant decreased to a = 0.416 nm. Otherwise, no diffraction peaks were observed for the as-grown chromium oxide samples, indicating that they were amorphous as reported for analogous layers prepared at room temperature [25,26]. After heating at 300 • C or above, diffraction peaks evidenced hexagonal Cr 2 O 3 (JCPDS 72-3533) with a mean crystallite size of 55 nm and lattice parameters a = 0.492 nm and c = 1.359 nm.…”

Study on Local Residual Stress in a Nanocrystalline Cr2O3 Coating by Micro-Raman Spectroscopy

“…Chromium trioxide (Cr 2 O 3 ), also known as chromium oxide, is used as a functional coating in many fields for its excellent properties such as high hardness, wear resistance, corrosion resistance and low coefficient of friction [1][2][3][4]. Cr 2 O 3 coatings are usually prepared by gas phase deposition.…”

RECORDING TECHNIQUE OF MASKS ON MULTILAYERED COATINGS (Part 1)

“…Таковыми являются, например, фотошаблоны с маскирующим слоем из смеси хрома и тонкой пленки оксида хрома [1]. Хотя, методы получения и характеристики тонких пленок оксида хрома изучены во многих работах, например [1][2][3], при изготовлении и конкретном практическом применении таких пленок необходимо более детальное исследование оптических свойств получаемых пленок оксида хрома, например, для разработки технологий изготовления масок, устраняющих проблему оплавления краев субмикронных дифракционных структур при сканировании их сфокусированным лазерным излучением [4,5]. Тем самым устраняется проблема локальной дифракции и интерференции световой волны на дифракционной структуре и на краях элементов, многократных отражений световой волны от контактирующих поверхностей в толще фоторезиста.…”