Fabrication and broadband ferromagnetic resonance studies of freestanding polycrystalline yttrium iron garnet thin films

Lei Zhang,Dainan Zhang,Shuai Liu,Hao Meng,Zhiyong Zhong,Bo Liu,Huaiwu Zhang,Xiaoli Tang,Mingming Li,Lichuan Jin

doi:10.1063/5.0054595

Abstract

Flexible magnetic materials and devices with basic functional properties are highly desirable for flexible electronic applications in wearable products and implantable systems. In this work, a freestanding polycrystalline yttrium iron garnet (YIG) thin film with strong magnetism has been synthesized by pulsed laser deposition using a water-dissolvable Sr3Al2O6 sacrificial layer, and the magnetism of the resulting freestanding film was confirmed by a vibrating sample magnetometer and broadband ferromagnetic resonance spectroscopy. When transferred to a support layer using a thermal release tape, the flexible polycrystalline YIG thin film exhibits a lower damping constant α and larger magnetocrystalline anisotropy, in contrast to the polycrystalline heterostructure of YIG, which arises due to stress release. Thus, this work offers a viable solution for flexible YIG thin films that can be used in a number of applications.

Highlights

There has been great demand for flexible electronic materials and devices in wearable products and implantable systems[1,2] due to various applications, such as flexible display,[3] Flexible Radio Frequency Identification (RFID),[4] and artificial neural networks.[5]
A freestanding polycrystalline yttrium iron garnet (YIG) thin film with strong magnetism has been synthesized by pulsed laser deposition using a water-dissolvable Sr3Al2O6 sacrificial layer, and the magnetism of the resulting freestanding film was confirmed by a vibrating sample magnetometer and broadband ferromagnetic resonance spectroscopy
Flexible thermal release tape (TRT) was pasted on the top of the SAO/GGG/YIG heterostructure, acting as a support layer to maintain the integrity of the GGG/YIG thin film after separation

Summary

INTRODUCTION

There has been great demand for flexible electronic materials and devices in wearable products and implantable systems[1,2] due to various applications, such as flexible display,[3] Flexible Radio Frequency Identification (RFID),[4] and artificial neural networks.[5]. In contrast to the heterostructure, after deposition, the static and dynamic magnetic properties of a freestanding polycrystalline YIG thin film changed significantly. We attributed this change to stress release during transfer to a thermal release tape (TRT). This work provides a new method for preparing freestanding YIG films

EXPERIMENTAL SECTION

Characteristics of structure and magnetic properties

RESULTS AND DISCUSSION

CONCLUSION