利用射频磁控溅射技术在不同工作气压和不同基底偏压条件下在Si(100)基底上设计合成了ZrB2/AlN纳米多层膜。利用X射线衍射、扫描电子显微镜、纳米力学测试系统和表面轮廓仪分析了工作气压和基底偏压对薄膜的微结构和机械性能的影响。结果表明:大部分ZrB2/AlN多层膜的纳米硬度与弹性模量值高于两种个体材料的混合值。当工作气压为0.4Pa,基底偏压为-60 V时,制备的薄膜具有最高的硬度(36.8 GPa)、最高的弹性模量(488.7 GPa)和最高的临界载荷(43.6 mN)。基底偏压的升高和工作气压的降低会使沉积粒子的动能提高,引起薄膜表面原子迁移率提高,导致薄膜的原子密度提高,起到位错钉扎的作用,晶粒尺度也被限制在纳米尺度,这些均对提高薄膜的硬度和抗裂强度起到了作用。
The ZrB2/AlN multi-layers were grown by RF magnetron sputtering on Si(100)substrates.Its microstructures were characterized with X-ray diffraction,scanning electron microscopy and conventional surface probes.The impacts of the growth conditions on its microstructures and mechanical properties were studied.The results show that the nano-hardness and elastic modulus of the ZrB2/AlN multi-layers are higher than those of the rule-of-mixture of monolithic ZrB2 and AlN coatings,and that the higher bias voltage and lower pressure significantly affects its microstructures and mechanical properties.For instance,at a pressure of 0.4 Pa,a bias of-60 V,the ZrB2/AlN multi-layers have a highest hardness of 36.8 GPa,a maximum modulus of 488.7 GPa,and a critical fracture load of 43.6 mN.Possible mechanisms responsible for the increased surface compactness were also tentatively discussed.