An integrated tunable isolator based on NiZn film fabricated by spin-spray plating

Rongdi Guo,Zhiguang Wang,Hwaider Lin,Nian Xiang Sun,Yuan Gao,Zhong Yu,Wei Shi,Zhongwen Lan

doi:10.1063/1.5006722

Abstract

An innovative type of tunable isolator with a planar comb-like microstrip transmission line, which generate circular polarization magnetic field, has been realized with polycrystalline NiZn ferrite thick films fabricated by spin-spray plating (SSP) process with thickness of 10μm. The phase compositions, microstructure, magnetic hysteresis loop, and ferromagnetic resonance (FMR) linewidth of NiZn ferrite thick films have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM) and electron spin resonance (ESR) spectrometer, respectively. The NiZn ferrite thick films possess 4800Gauss saturation magnetization and 190Oe FMR linewidth measured at X-band. With an in-plane dc magnetic bias perpendicular to the comb-like microstrip transmission line, the transmission direction of left-hand circular polarization (LHCP) and right-hand circular polarization (RHCP) were proved to be opposite. The non-reciprocal ferromagnetic resonance absorption leads to 11.6dB isolation and 5.78dB insertion loss at 17.57GHz with magnetic bias field of 3.5kOe. Furthermore, with external in-plane magnetic fields range from 0.5kOe to 3.5kOe, the central frequency was tuned from 5.63GHz to 17.57GHz. The state-of-the-art tunable isolator with a planar comb-like microstrip transmission line exhibit a great potential to be applied in different microwave components and radar system.

Highlights

Due to the demand of compact, lightweight, ultra-wideband, minimized power consumption, and large power-handling capability, the tunable devices are desired for the modern communication systems, radars, and metrology systems
Impedance matching, and protection of transceiver, tunable isolators play a key role in microwave components and systems.[1,2]
056620-5 Guo et al In Fig. 2(a), the X-ray diffraction (XRD) patterns of NiZn ferrite thick films agree well with the powder diffraction file of JCPDS No.08-0234, and the XRD patterns indicated the formation of single cubic spinel phase

Summary

Introduction

Due to the demand of compact, lightweight, ultra-wideband, minimized power consumption, and large power-handling capability, the tunable devices are desired for the modern communication systems, radars, and metrology systems. Rongdi Guo,1,2,a Hwaider Lin,[1] Wei Shi,[1] Yuan Gao,[1] Zhiguang Wang,[1] Nian Xiang Sun,[1] Zhong Yu,[2] and Zhongwen Lan2 1Department of Electrical and Computer Engineering, Northeastern University, Boston, MA 02115, USA 2State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, China (Presented 9 November 2017; received 27 September 2017; accepted 8 November 2017; published online 26 December 2017)

Results

Conclusion