Demonstration of Integrated Solenoid Transformer Balun in Glass Substrate Utilizing TGVs

This paper presents the implementation of a solenoid transformer balun within a glass substrate using through-glass vias (TGVs). We designed a Marchand type balun, based on a 3D solenoid transformer and integrated into a glass substrate, using TGVs realized through the laser induced deep etching process. The fabricated balun features a compact footprint of 1.18 × 0.61 × 0.46 mm3, good magnitude and phase balance performance, and a wide frequency bandwidth. The measured results align well with the simulations, showing a fractional bandwidth of over 50%, a common mode rejection ratio (CMRR) above 23dB, and a low insertion loss of less than 1.15dB, reaching a minimum of 0.45dB.