EBL制备用于气体传感器的SAW延迟线的方法

Fabrication of SAW Delay-line for Gas Sensors by EBL

电子束光刻(EBL)具有高的分辨率,能制备具有亚微米尺寸的声表面波(SAW)器件。一种采用EBL技术制备用于气体传感器的具有亚微米尺寸的SAW延迟线的方法:首先利用EBL在压电衬底上获得叉指换能器(IDT)的电子抗蚀剂图形;然后用剥离工艺制作出IDT电极。通过邻近效应校正和提高场拼接精度,制作的叉指电极具有一致性,电极形貌好。相对于干法刻蚀工艺,剥离工艺避免了对压电衬底表面的物理损伤。该技术为实现特征尺寸达到百纳米级的更高工作频率SAW器件的制造提供了很好的途径。

Sub-micron surface acoustic wave（SAW） devices can be fabricated by the electron beam lithography（EBL） for high resolution.An approach to fabricate sub-micron SAW delay-line for gas sensors by using EBL and metal lift-off was presented as follows： first to get interdigital transducer（IDT） resist pattern on the piezoelectric substrate by EBL;then to obtain IDT electrodes using metal lift-off.By the correction of proximity effect and the improvement of field splicing accuracy in EBL,consistent and well-structured IDT was obtained.Compared with the dry etching,the metal lift-off process avoids physical damages on the substrate surface.This is a good method for the fabrication of higher frequency SAW devices with hundred-nanometer feature size.