A High Coupling Coefficient Transformer Based on Coaxial TSV

A coaxial Through-Silicon Vias (TSV) transformer structure is proposed in this paper. The primary and secondary windings of the transformer surround each other to promote the coupling between the windings and reduce the leakage of magnetic flux. In addition, the area of primary and secondary windings is shared, reducing the chip area occupation. Compared with transformers in other literatures, the main advantage of this structure is that the coupling coefficient can reach more than 0.98, and the on-chip area is only 0.008 m$\mathrm{m}^{2}$.