Fabrication and characterization of surface micromachined stacked transformer on glass substrate

On-chip micro-transformer with square interwinding coil has been developed. The transformer consists of stacked spiral coil which is fabricated on high resistive glass substrate using MEMS technology. The device is fabricated using simple surface micromachining process including an additional bonding process for integration purpose. The performance of the micro-transformer is illustrated through low and high frequency measurements and compared with conventional Si-based micro-transformer. The results show that the RF performance of the glass-based transformer is improved compared to that of silicon-based transformer highlighting a good prospect for the future 3-dimensional RF–MEMS device application.