Preparation and Characterization of Sprayed-Yttrium Oxyfluoride Corrosion Protective Coating for Plasma Process Chambers

Abstract

This study investigates the microstructure, mechanical and electrical properties of dense yttrium oxyfluoride (YOF) coatings fabricated by the atmospheric plasma spraying technique. Transmission electron microscopy and X-ray diffraction analysis revealed a well crystallized YOF coating with preferred orientations. The YOF coatings were more porous (approximate porosity 0.5%), with higher hardness (290 ± 30 HV), lower electrical resistivity (1016 Ω⋅cm), and breakdown voltage (5.57 kV), than conventional yttrium-fluoride plasma-protective coating. These results indicate the potential of the YOF coating as a novel antiplasma and corrosion-resistant ceramic.

Contamination Particle Behavior of Aerosol Deposited Y2O3 and YF3 Coatings under NF3 Plasma

“…Among ceramic coating materials for preventing plasma corrosion, Y 2 O 3 is widely used for inner parts of the chamber because of its low etching rate and low chemical reactivity. Recently, YOF and YF 3 have also drawn attention as ceramic coating materials for parts owing to their ability to suppress chemical reactions with fluoridated gases such as CF 4 and NF 3 [8][9][10][11][12][13]. Nevertheless, there have been few reports about the behavior of contamination particles by plasma etching [14].…”

Plasma Etching Behavior of YOF Coating Deposited by Suspension Plasma Spraying in Inductively Coupled CHF3/Ar Plasma

“…The porosity of the YOF coating affects its hardness. The Vickers hardness of the YOF coating in Figure 3 was 553 ± 60 HV, which is much higher than 290 ± 30 HV for the YOF coating deposited by atmospheric plasma spraying (APS) reported recently by Lin et al [18] and 69.34 ± 4 HV (0.68 ± 0.04 GPa) for the YOF coating fabricated by hot pressing reported by Tsunoura et al [10]. Figure 4 shows the XRD peaks of the YOF coating.…”

Contamination Particles and Plasma Etching Behavior of Atmospheric Plasma Sprayed Y2O3 and YF3 Coatings under NF3 Plasma

“…The disc-like substrates were made of Al alloy 6061 and had a diameter of 76 mm and thickness of 3 mm. The substrates were then coated with Y 2 O 3 and YO 0.6 F 2.1 by atmospheric plasma spraying (APS) [23][24][25][26][27][28][29][30][31], with the use of a plasma spray system (Mettech's Axial III, Northwest Mettech Corp., North Vancouver, BC, Canada), where the Y 2 O and YF 3 were in a powder form (99.99%, D50 = 30 µm, Shin-Etsu, Tokyo, Japan). The sprayed coatings of Y 2 O 3 and YO 0.6 F 2.1 were respectively 110 and 70 µm thick.…”

“…Another advantage is that NF 3 is almost fully dissociated in the discharge, which results in a high etching rate [11][12][13][14]. The erosion behaviors of Y 2 O 3 , YOF, and YF 3 coatings in CF 4 /O 2 /Ar plasmas have been reported in previous works [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34]. However, there have been no studies on the corrosion behavior of the yttrium-based materials or contamination particles generated from them in NF 3 plasmas.…”