Development of Gyromagnetic and Dielectric Materials and Module for Microwave Application

摘要

For microwave components in a communication system, the toroid module is composed of gyromagnetic yttrium iron garnet (Y3Fe5O12 or YIG) elements and TiO2 (ε≈100) dielectric elements; the transformer module is composed of Mg2SiO4 (ε≈6) and BaTi4O9 (ε≈38) dielectric elements. This research starts from the perspective of establishing measurement instruments and analysis methods to overcome the bottleneck of high-frequency microwave characteristics analysis, and then investigate the optimized formulations and process conditions of the gyromagnetic and dielectric materials for the microwave characteristics of the desired frequency band. According to the selected operational frequency band, the appropriate Mn-Al substituted YIG quarter nary system is designed for gyromagnetic elements use. Besides, the three dielectric materials TiO2, Mg2SiO4 and BaTi4O9 with suitable additives are determined to meet the requirements for toroid module and transformer module, respectively. Subsequently, all materials and processes are integrated to develop the toroid and transformer modules and assemble into required microwave components. Finally, in accordance with user needs, module production and component assembly mass production technologies have been set up to meet the strict requirement of magnetic properties and microwave component characteristics: (1) saturation magnetization (4πMs) = 690±20 Gauss; (2) the squareness of hysteresis loop curve > 0.89; (3) the ferromagnetic resonance linewidth (ΔH)≤ 30; (4) the spin-wave resonance linewidth (ΔHk) ≥ 4; (5) the insertion loss (S21) < 0.9dB; (5) the reflection loss (S11)>16dB; (7) the phase shift deviation at different testing temperature (@23°C, 43°C, 64°C) < 5°. With the public's attention, the 5G system would be fully commercialized in 2020, which will bring the commercial application of this microwave module developed by this study.