Enhanced high-selectivity miniaturized bandpass filter using stacked glass-based IPD technology

Abstract

This paper presents a fifth-order inverse Chebyshev bandpass filter (BPF) operating at 600-840 MHz, realized using a stacked glass-based Integrated Passive Device (IPD) technology featuring Through-Glass-Vias (TGVs). The architecture employs a vertically stacked topology that enables the independent optimization of 3D TGV inductors and Metal-Insulator-Metal (MIM) capacitors, which are integrated via a high-precision chip-to-wafer bonding process. The fabricated BPF achieves an exceptionally compact footprint of 0.012λ₀ × 0.008λ₀, a sharp shape factor (SF) of 2.62, and a low insertion loss of 1.26 dB. These results represent a superior combination of miniaturization and selectivity compared to other filters realized on competing substrates. This work demonstrates a scalable methodology for co-integrating high-performance passive components on glass interposers, advancing the development of 2.5D/3D ultra-high-density heterogeneous systems by significantly enhancing integration density and RF performance.