マイクロ円環圧縮試験法によリ測定したSiC薄膜のはく離強度に及ぼす膜厚の影響

抄録

In order to investigate the influence of SiC film thickness on interfacial fracture toughness, SiC films with thicknesses of 1μm, 2μm and 3μm were sputter coated on stainless steel rings with a diameter of 20mm, and a micro ring-compression test was carried out by gradually applying horizontal compression load to the specimen with observing deformation and delamination behavior. The result showed that the curvature of the specimen increased with increasing compression load, and delamination of the SiC film occurred with further increasing load after cracking of the film perpendicular to the loading direction. Scanning electron microscopic observation result showed that delamination of the SiC film occurred from the interface. Obtained interfacial fracture toughness monotonically increased with increasing film thickness. To discuss the reason for the change of the interfacial fracture toughness, X-ray residual stress measurement was carried out. The result showed that compressive residual stress was introduced in the films and the amount of the compressive residual stress increased with increasing film thickness. It was presumed that the interfacial fracture toughness was increased by the compressive residual stress.