Optimizing the Design of Surface-Acoustic-Wave Ring Resonator by Changing the Interdigitated Transducer Topology

Introduction. Previous works considered the frequency characteristics and methods for fixing sensitive elements in the form of a wave ring resonator on surface acoustic waves in a housing made of various materials, as well as the influence of external factors on sensitive elements. It was found that the passband in such a case is sufficiently wide, which can affect adversely signal detection when measuring acceleration using the sensitive element under development. Therefore, it has become relevant to reduce the sensitive element’s bandwidth by changing the design of the interdigitated transducer (IDT).

Aim. To demonstrate an optimal topology for an IDT with a low bandwidth, leading to improved signal detection when acceleration affects the sensitive element.

Materials and methods. The finite element method and mathematical processing in AutoCAD and in COMSOL Multiphysics.

Results. Nine topologies of IDT are proposed. All these types were investigated using the COMSOL Multiphysics software on lithium niobate substrates, which material acts as a sensitive element. The frequency characteristics are presented. The data obtained allowed an optimal design of the ring resonator to be proposed: an IDT with rectangular pins without selective withdrawal.

Conclusion. Self-generation in a ring resonator can be performed by withdrawing no more than one pair of IDTs for 10 or more periods. In this case, the withdrawal of IDTs should be uniform. With an increase in the number of IDT withdrawals, the geometry of the ring resonator is violated, and the wave leaves the structure. The presence of a shared bus keeps the surface acoustic wave inside the IDT structure, and the narrowing of the periods towards the inner part of the structure makes it possible to improve the frequency characteristics of the ring resonator on surface acoustic waves.

1. Preeti M., Guha K., Baishnab K. L., Sastry A. S. C. S. Design and Analysis of a Capacitive MEMS Accelerometer as a Wearable Sensor in Identifying Low-Frequency Vibration Profiles. Modern Techniques in Biosensors: Detection Methods and Commercial Aspects. Ed. by G. Dutta, A. Biswas, A. Chakrabarti. Singapore, Springer, 2021, pp. 37–61. doi: 10.1007/978-981-15-9612-4_2

2. Tang W., Chen C. Motion Recognition System of Table Tennis Players Based on MEMS Sensor. Multimedia Technology and Enhanced Learning. ICMTEL 2021. Ed. by W. Fu, Y. Xu, S.-H. Wang, Y. Zhang. Cham, Springer, 2021, pp. 128–141. doi: 10.1007/978-3-030-82565-2_11

3. Petrak O., Schwarz F., Pohl L., Reher M., Janicke C., Przytarski J., Senger F., Albers J., Giese T., Ratzmann L., Blicharski P., Marauska S., Wantoch T., Hofmann U. Laser Beam Scanning Based AR-Display Applying Resonant 2D MEMS Mirrors. Proc. SPIE. 2021, vol. 11765, pp. 1–18. doi: 10.1117/12.2579695

4. Zhou G., Lim Z. H., Qi Y., Zhou G. Single-Pixel MEMS Imaging Systems. Micromachines. 2020, vol. 11, no. 2, p. 219. doi: 10.3390/mi11020219

5. Kourani A., Yang Y., Gong S. A Ku-Band Oscillator Utilizing Overtone Lithium Niobate RF-MEMS Resonator for 5G. IEEE Microwave and Wireless Components Lett. 2020, vol. 30, no. 7, pp. 681–684. doi: 10.1109/LMWC.2020.2996961

6. Wu Z., Wang J., Bian C., Tong J., Xia S. A MEMSBased Multi-Parameter Integrated Chip and Its Portable System for Water Quality Detection. Micromachines. 2020, vol. 11, no. 2, p. 63. doi: 10.3390/mi11010063

7. iPhone 12 Pro and iPhone 12 Pro Max – Technical Specifications. Available at: https://www.apple.com/uk/iphone-12-pro/specs/ (accessed 07.11.2021)

8. DualSense wireless controller. The innovative new controller for PS5. Available at: https://www.playstation.com/en-gb/accessories/dualsense-wireless-controller/ (accessed 07.11.2021)

9. PlayStation VR. Technical Specifications. Available at: https://www.playstation.com/en-gb/ps-vr/tech-specs/ (accessed 07.11.2021)

10. Momentus 7200.2. Product Overview. Available at: https://www.seagate.com/docs/pdf/marketing/po_momentus_7200_2.pdf (accessed 07.11.2021)

11. Car DVR camera system: PROTECT 802 (2 channels, GPS, accelerometer). Available at: https://www.dipolnet.com/car_dvr_camera_system_protect_802_2_channels_gps_accelerometer__M70802.htm (accessed 07.11.2021)

12. Morgan D., Paige E. G. S. Propagation Effects and Materials. Surface Acoustic Wave Filters. 2nd ed. Oxford, Academic Press, 2007, pp. 87–113. doi: 10.1016/B978-0-12-372537-0.X5000-6

13. Gupalov V., Kukaev A., Shevchenko S., Shalymov E., Venediktov V. Physical Principles of a Piezo Accelerometer Sensitive to a Nearly Constant Signal. Sensors. 2018, vol. 18, no. 10, 3258, pp. 1–5. doi: 10.3390/s18103258

14. Durukan Y., Shevelko M., Peregudov A., Popkova E., Shevchenko S. The Effect of a Rotating Medium on Bulk Acoustic Wave Polarization: From Theoretical Considerations to Perspective Angular Motion Sensor Design. Sensors. 2020, vol. 20, no. 9, 2487, pp. 1–11. doi: https://doi.org/10.3390/s20092487

15. Product Finder. PCB Piezotronics. Available at: https://www.pcb.com/products/product-finder?tx=15 (accessed 07.11.2021)

16. Constantinoiu I., Viespe C. Development of Pd/TiO2 Porous Layers by Pulsed Laser Deposition for Surface Acoustic Wave H2 Gas Sensor. Nanomaterials. 2020, vol. 10, no. 4, 760, pp. 1–10. doi: 10.3390/nano10040760

17. Li X., Wang W., Fan S., Yin Y., Jia Y., Liang Y., Liu M. Optimization of SAW Devices with LGS/Pt Structure for Sensing Temperature. Sensors. 2020, vol. 20, no. 9, 2441, pp. 1–13. doi: 10.3390/s20092441

18. Tang Z., Wu W., Gao J., Yang P., Luo J., Fu C. Water Pressure Monitoring Using a Temperature-Compensated WP-SAW Pressure Sensor. IEEE 18th Intern. Conf. on Industrial Informatics (INDIN). 2020, pp. 354–357. doi: 10.1109/INDIN45582.2020.9442222

19. Shevchenko S. Y., Khivrich M. A., Markelov M. A. Ring-Shaped Sensitive Element Design for Acceleration Measurements: Overcoming the Limitations of Angular-Shaped Sensors. Electronics. 2019, vol. 8, 141, pp. 1–12. doi: 10.3390/electronics8020141

20. Shevchenko S. Y., Mikhailenko D. A., Markelov O. A. Comparison of AlN vs. SIO2/LiNbO3 Membranes as Sensitive Elements for the SAW-Based Acceleration Measurement: Overcoming the Anisotropy Effects. Sensors. 2020, vol. 20, no. 2, 464, pp. 1–13. doi: 10.3390/s20020464