Wafer-Scale Flexible Surface Acoustic Wave Devices Based on an AlN/Si Structure
ZHANG Cang-Hai, YANG Yi, ZHOU Chang-Jian, SHU Yi, TIAN He, WANG Zhe, XUE Qing-Tang, REN Tian-Ling**
Institute of Microelectronics, Tsinghua University, Beijing 100084 Tsinghua National Laboratory for Information Science and Technology (TNLIST), Tsinghua University, Beijing 100084
Abstract：Wafer-scale flexible surface acoustic wave (SAW) devices based on AlN/silicon structure are demonstrated. The final fabricated devices with a 50μm-thickness silicon wafer exhibit good flexibility with a bending curvature radius of 8 mm. Measurements under free and bending conditions are carried out, showing that the central frequency shifts little as the curvature changes. SAW devices with central frequency about 191.9 MHz and Q-factor up to 600 are obtained. The flexible technology proposed is directly applied to the wafer silicon substrate in the last step, providing the potential of high performance flexible wafer-scale devices by direct integration with mature CMOS and MEMS technology.
2013, Vol. 30 
