학술논문

Bragg Reflector Type Shear Mode BAW Transformer Based on c-Axis Zig-Zag ScAlN Multilayer for Rectifying Antenna
Document Type
Periodical
Source
IEEE Sensors Letters IEEE Sens. Lett. Sensors Letters, IEEE. 7(11):1-4 Nov, 2023
Subject
Components, Circuits, Devices and Systems
Robotics and Control Systems
Communication, Networking and Broadcast Technologies
Signal Processing and Analysis
Transformers
Films
Nonhomogeneous media
Substrates
Sensors
Rectennas
RF signals
Physical sensors
Internet-of-Things (IoT)
piezoelectric transformer
rectenna
ScAlN
zig-zag
Language
ISSN
2475-1472
Abstract
Radio frequency (RF) signals can be converted to dc signals using an antenna and diode (which is so called rectenna). In a long-distance wireless transfer, weak RF signals cannot exceed the threshold voltage of the diodes in the rectenna, making RF-DC conversion very inefficient. This letter proposes resonator type GHz piezoelectric transformer based on c -axis zig-zag ScAlN films. Solidly mounted resonator (SMR) type transformer using an acoustic Bragg reflector enables a wider bandwidth operation than film/substrate type transformer we reported previously. As a result, zig-zag multilayers which was oriented 180° symmetrically on the acoustic Bragg reflector was fabricated by oblique RF magnetron sputtering. In addition, voltage gain of 2.7 and the fractional bandwidth of 3.2% which was 46 times wider than that of film/substrate type transformer were observed.