Herein, silica aerogel films were used in the fabrication of surface acoustic wave(SAW) filters for the first time. Firstly, silica aerogel films with various silica sol driptimes were prepared and characterized. According to spectroscopic ellipsometry, therefractive index of an aerogel film with a silica sol drip time of 9 min decreased by5.9% compared with a film with sol drip time of 18 min in the intermediate region ofthe sample. The increase in sol drip time led to an increase in particle size andthickness, and a decrease in pore size. Secondly, four different types of SAW filterswere designed, i.e. covered with either air, poly(dimethylsiloxane) (PDMS), PDMSfilled with silica aerogel powder, or a silica aerogel film. Addition of silica aerogelpowder to PDMS increased the bandwidth of the resulting SAW filter to 2.362 MHz,increased its central frequency to 0.001 GHz and decreased its insertion loss to 1.545dB. Although they had low porosity, the SAW filters covered with silica aerogel filmshad a bandwidth of 60.586 MHz, a central frequency of 2.447 GHz, a Q value of 40.073, and the largest insertion loss of –15.397 dB. SAW filters with silica aerogel films withvarious sol drip times were also tested. The results indicated that more porous thesilica aerogel films, stronger is the signal strength and smaller is the insertion lossof the SAW filter.

在此，二氧化硅气凝胶薄膜首次用于表面声波（SAW）滤波器的制造。首先，制备并表征了具有不同硅溶胶滴落时间的二氧化硅气凝胶薄膜。根据椭圆偏振光谱法，样品中间区域硅溶胶滴加时间为9 min的气凝胶膜的折射率比溶胶滴加时间为18 min的气凝胶膜的折射率降低了5.9%。溶胶滴落时间的增加导致颗粒尺寸和厚度的增加，以及孔径的减小。其次，设计了四种不同类型的 SAW 滤波器，即覆盖有空气、聚（二甲基硅氧烷）(PDMS)、填充有二氧化硅气凝胶粉末的 PDMS 或二氧化硅气凝胶薄膜。向 PDMS 添加二氧化硅气凝胶粉末可将所得 SAW 滤波器的带宽增加至 2.362 MHz，将其中心频率提高到 0.001 GHz，并将其插入损耗降低到 1.545dB。虽然孔隙率低，但覆盖二氧化硅气凝胶膜的SAW滤波器带宽为60.586 MHz，中心频率为2.447 GHz，Q值为40.073，最大插入损耗为–15.397 dB。还测试了具有各种溶胶滴落时间的二氧化硅气凝胶膜的 SAW 过滤器。结果表明，二氧化硅气凝胶薄膜的孔隙越多，信号强度越强，声表面波滤波器的插入损耗越小。还测试了具有各种溶胶滴落时间的二氧化硅气凝胶膜的 SAW 过滤器。结果表明，二氧化硅气凝胶薄膜的孔隙越多，信号强度越强，声表面波滤波器的插入损耗越小。还测试了具有各种溶胶滴落时间的二氧化硅气凝胶膜的 SAW 过滤器。结果表明，二氧化硅气凝胶薄膜的孔隙越多，信号强度越强，声表面波滤波器的插入损耗越小。