六方氮化硼薄膜制备及其压电响应的研究

Research on preparation and piezoelectric response of hexagonal boron nitride films

采用射频(RF)磁控溅射的方法,通过改变工艺参数在n型Si(100)片上制备六方氮化硼(h-BN)薄膜。通过傅立叶红外(FTIR)光谱仪,X射线衍射(XRD)仪进行结构表征,原子力显微镜(AFM)进行表面形貌和压电性能表征。测试结果表明,在射频功率为300 W、衬底温度为500℃、工作压强在0.8Pa、N2与Ar流量比为4∶20和衬底偏压在-200V时制备的六方BN薄膜具有高纯度、高c-轴择优取向,颗粒均匀致密,粗糙度为2.26nm,具有压电性并且压电响应均匀,符合高频声表面波器件基片高声速、优压电性要求。薄膜压电性测试研究表明,AFM的PFM测试方法适用于纳米结构半导体薄膜的压电性及其压电响应分布特性的表征。

Boron nitride （BN） films for high-frequency SAW devices were deposited on n-type Si（100） wafers by changing the process parameters using RF magnetron sputtering. The structure of hexagonal boron nitride （h-BN） films was investigated by Fourier transform infrared （NFIR） spectroscopy and X- ray diffraction （XRD） spectra. The surface morphology and piezoelectric properties of h-BN film were characterized by atomic force microscopy （AFM）. And the results show that when the RF power is 300 W, the substrate temperature is 500 ℃,working pressure is 0.8 Pa,nitrogen and argon flow ratio is 4 20 and negative substrate bias is -200 V,h-BN films are in high purity and c-axis oriented,and the partides are uniform and compact, and the roughness is 2.26 nm with even piezoelectric response, meeting the requirements of high sound propagation speed and excellent piezoelectric properties for high frequency SAW devices. The studies of piezoelectric test of thin films have shown that the PFM test method of atomic force microscopy is suitable for characterizing piezoelectric properties and piezoelectric response distribution of nano-structure semiconductor thin films.