Surface micromachined on-chip transformer fabricated on glass substrate

Abstract

On-chip micro-transformer on high resistive glass substrate has been developed. The transformer consists of stacked spiral coil with square interwinding coil structure which is fabricated using surface micromachining technique. The performance of the micro-transformer is illustrated through low and high frequency measurements. The characteristics of glass based transformer are 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. The process fabrication of the device is simple, highlighting a good prospect for the future threedimensional RF-MEMS device application.

Geometrical analysis of planar coil design for fluxgate magnetometer

“…Similar to the inductance characteristic simulation, it is shown that the measured inductance value decreases rapidly at the frequency range between 450 and 600 MHz before it reaches the resonance point. It also is found that the magnetic coupling is relatively low compared to the stack structure reported in our previous work (Yunas et al 2009). The low coupling is possibly due to a high flux leakage on the planar coil structure.…”

“…The stack structure will reduce the number of coil winding on one layer while keeping the same total inductance. The stack structure also provides high magnetic coupling while keeping small chip area (Yunas et al 2009). …”

Design, fabrication and testing of sandwich coupled inductors

“…Compared to the previously reported single layer coupled coil structures, planar coupled inductor with stacked coil structure exhibits several advantages such as higher inductance value due to higher winding number, simple fabrication and higher coupling value due to the magnetic coupling at both lateral and vertical directions (Yunas et al 2009). …”

Innovations in Magnetic Materials

“…15a and b (Yunas et al 2009;Yunas and Majlis 2008). Single deposition of the magnetic core material provides a completely closed magnetic circuit and minimizes leakage flux.…”