TC-SAW SiO2温补层性能研究

Study on the Performance of SiO2 Thermal Compensation Layer for Temperature-Compensated Surface Acoustic Wave

摘要:

为制备高性能的TC-SAW SiO2 温补层,分别采用电子束蒸发镀膜和反应磁控溅射制备SiO2 薄膜,研究两种制备工艺对SiO2 薄膜致密性、表面粗糙度及弹性模量的影响。采用扫描电子显微镜、原子力显微镜、X线衍射仪对SiO2 薄膜的形貌和晶体结构进行分析。采用椭偏仪测试薄膜折射率及腐蚀后的膜厚变化量,并通过纳米压痕仪测量计算薄膜的硬度和弹性模量。结果表明,反应磁控溅射制备的SiO2 薄膜更致密、薄膜表面粗糙度更小、弹性模量更大。采用反应磁控溅射制备的SiO2 薄膜作为TC-SAW温补层,可以获得频率温度系数为-8.6× 10-6/℃的TC-SAW器件。

Abstract:

To prepare high-performance SiO2 thermal compensation layers for temperature-compensated surface acoustic wave (TC-SAW), SiO2 thin films were prepared using electron beam evaporation coating and reactive mag netron sputtering. The effects of the two preparation processes on the density, surface roughness, and elastic modu lus of SiO2 thin films were studied. The morphology and crystal structure of SiO2 films were analyzed using scan ning electron microscopy, atomic force microscopy, and X-ray diffraction. The refractive index and thickness chan ges of the thin film after corrosion were measured using an ellipsometer and the hardness and elastic modulus of the thin film were calculated using a nano-tracer. The results show that SiO2 prepared by reactive magnetron sputtering has a denser film, lower surface roughness, and higher elastic modulus. A TC-SAW device with a frequency temperature coef ficient of -8.6×10-6/℃ was obtained using a SiO2 thin film prepared by reactive magnetron sputtering.