MEMS-based inductor implementation for RF front end of mobile terminal

Abstract

There has been significant growth in the wireless market where new applications are accompanied with strict design goals such as low cost, low power dissipation and small form factor. Large capacity and range for new applications are the driving force for development of new standard such as third generation mobile system (3G). Recent research results show that the development that was not possible with current IC technology is made possible with MicroElectroMechanical Systems (MEMS) technology. Significant amount of research is taking place to replace the off-chip components with on-chip components to design a high performance receiver front end. The passive components such as switches, capacitors and inductors are integral part of RF front end. High quality (Q) inductors are used to design RF front-end components such as voltage-controlled oscillator (VCO) and low noise amplifier (LNA). However, they are the bottleneck in achieving the on-chip optimum components, because of Q factor dependence on parasitic effects, limiting the performance. In recent research publications different on-chip inductor structures such as coil, polygon, rectangular and stacked configurations have been suggested and used to implement high value of inductance. In this paper design and implementation issues of MEMS inductor are presented. The paper is divided in two sections, the first section presents the role of MEMS based passive components and second section presents design issues, implementation and analysis of different MEMS based inductors.

Design and implementation of an optimised wireless pressure sensor for biomedical application

“…Based on Eq. (14), the oscillator requirement for the capacitive sensor is: 120 dBc/Hz@1 MHz offset. The total tail current, controlled by transistor M N 3 as presented in Fig.…”

“…6. Advantages of MEMS devices include small size, high Q factor, low power consumption, high selectivity and compatible fabrication process [13][14][15]. The MEMS inductor is implemented using a simulator that models self-inductance and resistance including skin effects and substrate effects.…”

“…The MEMS inductors are also implemented using Coventor design suite. Reduced order models of the MEMS inductor are extracted using Coventorware's SpringMMElectrical, SpringMM-Mechanical and InertiaMM analysis in from of Verilog-A codes, and they are then imported to Cadence for co-simulation with the CMOS section of the oscillator [14].…”

Optimised MEMS-based reconfigurable VCO for a mobile receiver

“…4., the passive components, including inductors (L 1 , L 2 , L 3 and L 4 ), capacitors (C 1 , C 2 , C 3 and C 4 ) and switches (SW 1 , SW 2 , SW 3 and SW 4 ), are replaced by MEMS components. Advantages of MEMS devices include small size, high Q factor, low power consumption, high selectivity and compatible fabrication process [6,7]. The MEMS inductor is implemented by modelling its self-inductance and resistance including skin effects and substrate effects using a single balanced octagonal MEMS inductor with a center tap.…”