压电与声光, 2023, 45 (6): 800, 网络出版: 2024-01-04
提高单晶薄膜滤波器片内频率一致性的研究
Research on Improving Internal Frequency Consistency of Surface Acoustic Wave Filters Prepared by Piezoelectric-on-Insulator
压电单晶薄膜衬底 抗反射膜 曝光补偿 频率一致性 piezoelectric-on-insulator wafer antireflective film exposure compensation frequency consistency
摘要
研究了常规光刻工艺下单晶薄膜晶圆制备声表面波滤波器的频率分散特性。结果表明,压电单晶薄膜的表面色差是引起频率分散性恶化的根本原因,采用抗反射膜工艺抑制衬底反射以及分区曝光工艺对不同色块进行曝光补偿,均能有效地提高片内频率一致性,频率2 MHz内包含最大器件数量占比,从常规曝光的48.81%提高到抗反射膜工艺的53.57%和分区曝光工艺的70.24%。
Abstract
The frequency dispersion of the surface acoustic wave (SAW) filters prepared by Piezoelectric-on-Insulator (POI) wafer under conventional photolithography process is investigated in this paper. The results show that the chromatism of the piezoelectric single crystal thin film is the fundamental reason for the deterioration of frequency consistency. In this work, we used bottom anti-reflection coating (BARC) technology to suppress the reflection from the wafer and partitioned the exposure regions to compensate different color blocks. Both the ways can effectively improve the frequency consistency of the SAW filters. The proportion of maximum device quantity in 2 MHz is improved from 48.81% in conventional exposure process to 53.57% in BARC technology and 70.24% in partition exposure progress.
>潘祺, 米佳. 提高单晶薄膜滤波器片内频率一致性的研究[J]. 压电与声光, 2023, 45(6): 800. WafersPAN Qi, MI Jia. Research on Improving Internal Frequency Consistency of Surface Acoustic Wave Filters Prepared by Piezoelectric-on-Insulator[J]. Piezoelectrics & Acoustooptics, 2023, 45(6): 800.