Effect of bias voltage on microstructure and nanomechanical properties of Ti films

In order to investigate nanomechanical properties of nanostructured Ti metallic material, pure Ti films were prepared by magnetron sputtering at the bias voltage of 0-140 V. The microstructure of Ti films was characterized by X-ray diffraction（XRD）, scanning electron microscopy（SEM） and high-resolution transmission electron microscopy（HRTEM）. It is interesting to find that the microstructure of pure Ti films was characterized by the composite structure of amorphous-like matrix embodied with nanocrystallines, and the crystallization was improved with the increase of bias voltage. The hardness of Ti films measured by nanoindentation tests shows a linear relationship with grain sizes in the scale of 6-15 nm. However, the pure Ti films exhibit a soft tendency characterized by a smaller slope of Hall-Petch relationship. In addition, the effect of bias voltage on the growth orientation of Ti films was discussed.

磁控溅射法制备纳米晶钛薄膜工艺研究

利用直流磁控溅射法在硅基底上沉积出纳米晶钛薄膜,研究了背底真空度、溅射功率和基底温度对纳米晶钛薄膜结构的影响。实验证明,当背底真空度高于8.8×10-5 Pa时,可制备出致密的纳米晶钛薄膜,当背底真空度低于2.0×10-4 Pa时,钛薄膜被氧化成一氧化钛薄膜;随着溅射功率的增大,纳米晶钛膜的晶粒尺寸呈线性增大,同时钛薄膜的取向也发生改变,表现出明显的(002)织构;随着温度的升高,钛薄膜织构取向发生改变,当温度为500℃时,钛薄膜被氧化为一氧化钛薄膜。制成平整钛薄膜的工艺条件为:背底真空度8.8×10-5 Pa,溅射功率200 W,基底温度室温。