Question

is a suspended inductor on a ceramic substrate for very high frequency electrical It was realized using MEMS techniques discussed in the class 1. (20) The following is a suspended inductor on Explain the reason why the inductor is suspended from the substrate. 4) the fabrication of the inductor using a fabrication flow-chart.

Answer 1

MEMS inductors find place along with the tunable capacitors. In normal planar inductor, the resistive metal lines and the dielectric losses in the substrate, contribute for the degradation of the Q factor and also cause fringing and parasitic capacitances.

1.The micromachined inductors with suspended metal structures offer very high Q factor resulting in high frequency performance of the systems. The dielectric losses due to the substrate as well as the parasitic capacitances and fringing due to the metal lines in the substrate can be avoided by suspending the structure over the substrate.

2.The fabrication techniques used to achieve inductors with high Q-factors and high inductances. More emphasis is given to the Q-factor since it has been the main focus in most reported studies.

Due to their compact size and compatibility with CMOS fabrication process. In particular, circular or rectangular spiral inductors have shown great inductance density per unit area. The improvement of the Q-factor of these inductors, however, has been the most challenging task due to the nature of the magnetic field generated by these inductors which is, in most cases, perpendicular to the substrate and induces eddy currents losses. Since CMOS fabrication does not support thick deposition of metal films, a MEMS thick electroplating process of the metal coil, in conjunction with the low-K layer, is usually used to achieve an even higher Q-factor.