The article reports the development of compact, high-performance spin-wave (SW) ladder filters using yttrium iron garnet (YIG) on gadolinium gallium garnet (GGG), specifically designed for next-generation 5G and 6G RF systems. Traditional SW and magnetostatic wave filters are limited by small bandwidths, large device sizes, and spurious modes, making them unsuitable for the high-frequency, wideband requirements of 6G (7–24 GHz).
The authors design third- and fifth-order SW ladder filters that achieve broad lithographically defined bandwidths up to 663 MHz, low insertion loss (2.54–5.78 dB), and strong spurious suppression, all while requiring only a single external magnetic bias. By engineering geometric contrasts between series and shunt resonators, the filters achieve frequency separations exceeding 600 MHz without multiple magnetic fields. Key features include high linearity (input-referred third-order intercept >11 dBm), frequency tuning over several octaves (7.08–21.6 GHz), and a miniaturized footprint (~1.566 mm² for third-order filters), suitable for wafer-scale fabrication (Fig. 1 and 3, pages 2–4).
The fabrication process employs deep Ar-ion etching, lithographically defined YIG resonators, electroplated gold transducers, and selective thinning of the GGG substrate to maximize effective coupling and Q-factors. The resulting devices demonstrate consistent performance and 100% yield across chips, with suppressed spurious modes and robust out-of-band rejection.
As a practical demonstration, the authors integrate a SW ladder filter into a frequency-agile radio receiver. The filter dynamically tracks the communication channel, filtering out-of-band interference, and preserving signal integrity for 20 Mbps quadrature amplitude-modulated (QAM) signals, even in the presence of strong nearby interference (Fig. 4, page 5).
In conclusion, these miniaturized, high-bandwidth, frequency-tunable SW ladder filters provide a scalable solution for 6G RF front-ends, enabling a reduction in filter arrays, packaging complexity, and system cost while supporting frequency-agile, interference-resilient communication.
OMeda (Shanghai Omedasemi Co.,Ltd) was founded in 2021 by 3 doctors with more than 10 years of experience in nanpfabrication. It currently has 15 employees and has rich experience in nanofabrication (coating, lithography, etching, two-photon printing, bonding) and other processes. We support nanofabrication of 4/6/8-inch wafers.
