射频磁控溅射超硬TiB2薄膜的T区结构特征

Zone T Structural Characterization of Superhard TiB_2 Thin Films Prepared by RF Magnetron Sputtering

用磁控溅射技术在钢基片上沉积出具有T区结构的TiB2薄膜,研究基片偏压对薄膜的影响。使用X射线衍射技术和扫描电镜分析薄膜的特性。发现在本研究工艺条件下,所有的薄膜均呈(001)晶面择优生长。当基片偏压在-50 V时,薄膜的硬度为50 GPa,抗塑性变形的能力为0.65 GPa。加大基片偏压,导致薄膜晶粒尺寸减小,同时薄膜的硬度和抗塑性变形的能力也下降。扫描电镜分析显示,基片温度对T区结构的影响是明显的,提高基片温度,当Ts/Tm=0.18时,薄膜中出现"等轴"结构。

This study reports the effect of bias on the Zone T structure of TiB2 films deposited on steel substrates using magnetron sputtering technique. X-ray diffraction, scanning electron microscopy analysis have been used to characterize the films＇ properties. The （001） crystal orientation is characteristic of the films irrespective of the deposition process in our work. Using the nanoindentation testing, the hardness and ratio H^3/E^＊2 values of the films are 50GPa and 0.65GPa under -50V bias. With increasing the negative bias voltage, the grain size decreases, the hardness and resistance to plastic deformation （ H^3/E^＊2 ） decrease as well. The SEM analysis shows that the substrate temperature has a strong effect on Zone T structure. An increase in the substrate temperature promotes ＂equiaxed＂ grain structure in TiB2 thin films as Ts/Tm is 0.18.