Mechanical Properties and Diffusion Barrier Performance of CrWN Coatings Fabricated through Hybrid HiPIMS/RFMS

Abstract

CrWN coatings were fabricated through a hybrid high-power impulse magnetron sputtering/radio-frequency magnetron sputtering technique. The phase structures, mechanical properties, and tribological characteristics of CrWN coatings prepared with various nitrogen flow ratios (fN2s) were investigated. The results indicated that the CrWN coatings prepared at fN2 levels of 0.1 and 0.2 exhibited a Cr2N phase, whereas the coatings prepared at fN2 levels of 0.3 and 0.4 exhibited a CrN phase. These CrWN coatings exhibited hardness values of 16.7–20.2 GPa and Young’s modulus levels of 268–296 GPa, which indicated higher mechanical properties than those of coatings with similar residual stresses prepared through conventional direct current magnetron sputtering. Face-centered cubic (fcc) Cr51W2N47 coatings with a residual stress of −0.53 GPa exhibited the highest wear and scratch resistance. Furthermore, the diffusion barrier performance of fcc CrWN films on Cu metallization was explored, and they exhibited excellent barrier characteristics up to 650 °C.

Diffusion Barrier Characteristics of WSiN Films

“…where a is the lattice constant for the (111), ( 200), (220), and (311) reflection; K is the constant; θ is the diffraction angle. The sheet resistance of the Cu/WSiN/Si samples was determined using a four-point probe [35]. The standard deviations for sheet resistance data were calculated from 3 measurements.…”

“…Figure 7 displays the sheet resistance of the Cu/WSiN/Si samples at the as-deposited state and after annealing in a vacuum for 1 h at various temperatures. The sheet resistance of these Cu/WSiN/Si samples decreased from 0.9-1.2 Ω/ to approximately 0.3 Ω/ after they were annealed at 500 • C because of the defect annihilation and grain growth of Cu films [35,45], and then the sheet resistance of the aforementioned samples was maintained at the level of 0.3 Ω/ up to 700 • C annealing. The sheet resistance of the aforementioned samples with crystalline WSiN barriers slightly increased to 0.4 Ω/ when annealed at 750 • C and abruptly increased to 28-94 Ω/ when annealed at 800 • C, which was accompanied by the formation of Cu 3 Si (Figure 4).…”

“…A 5-nm-thick TaWN film with a (111) orientation exhibited barrier properties against Cu diffusion at 500 • C in a vacuum for 1 h [34]. Crystalline CrWN films were applied as a diffusion barrier up to 650 • C in a vacuum for 1 h, as reported in a previous study [35]. In [36], a co-sputtered W 28 Si 24 N 48 film exhibited high oxidation resistance at 600 • C in an oxygen-containing atmosphere because of its amorphous structure and the formation of the SiO 2 scale, which implied its potential application for diffusion barriers.…”

Polyacrylate Decorating Poly(ethylene terephthalate) (PET) Film Surface for Boosting Oxygen Barrier Property

“…It divides the penetration into three steps: (1) the osmotic molecules dissolve into the membrane by the contact surface, (2) the osmotic molecules diffuse in the membrane under a concentration gradient, and (3) the osmotic molecules desorb at the other side of the membrane [7][8][9]. The second step is the principal process that affects the transfer process [10,11]. There are two models to explain diffusion [12][13][14].…”