BEOL embedded RF-MEMS switch for mm-wave applications

Abstract

We demonstrate for the first time the embedded integration of a Radio Frequency Microelectromechanical Systems (RF-MEMS) capacitive switch for mm-wave integrated circuits in a BiCMOS Back-end-of-line (BEOL). The switch shows state-of-the-art performance parameters. The ¿off¿ to ¿on¿ capacitance ratio is 1:10 providing excellent isolation in the mm-wave frequency range. Insertion loss and isolation are found to fall below 1.65 dB and to exceed 15 dB, respectively, in the frequency range of 60 GHz to 110 GHz. Feasibility of switch integration into single chip RF designs is demonstrated for a dual-band voltage controlled oscillator (VCO). No performance degradation was observed after ten billion hot-switching cycles

30 GHz RF-MEMS Dicke Switch Network and a Wideband LNA in a 0.25 µm SiGe BiCMOS Technology

“…Similarly, as for the MEMS SPST switch results shown in Fig. 3(b), a certain shift in frequency occurred between the measured and simulated |s21| data which may be explained by a variation in MEMS switch capacitance [23].…”

“…The SPST switch has 0.7 dB and 12 dB of measured transmission losses (ON and OFF state) at 30 GHz, respectively (0.4 dB and 15 dB simulated). Compared with the modelled switch data, a slight shift in frequency occurred in the measured transmission due to a variation in the MEMS switch capacitance [23].…”

A 60 to 77 GHz Switchable LNA in an RF-MEMS Embedded BiCMOS Technology

“…Using the same technology, a 3 to 4 GHz switchable voltage controlled oscillator has already been presented in [4], and this work extends the applicability to millimeter-wave frequencies, by presenting novel results of a 60 to 77 GHz switchable LNA. …”

“…It is realized by the removal of the SiO in the switch area by wet etching, which adds only one additional mask layer to the standard technology process. The released M3 membrane bends upward due to residual mechanical stress, which is optimized by rigorous mechanical simulations and process optimization [4]. When an actuation voltage is applied on the M1 electrodes, the membrane is pulled down making contact with the TiN layer above the M2 signal line.…”

Ultrathin TiN Membranes as a Technology Platform for CMOS‐Integrated MEMS and BioMEMS Devices

“…In a modifi cation of the architectural layer scheme presented here, the full metal stack may also be used for highfrequency MEMS applications like in radiofrequency switches. [ 24 ] In general, the design rules of TiN membranes allow their scaling to smaller dimensions by keeping the aspect ratio h / L constant, where h may even lie in the nm range. This opens the perspective for ultrathin TiN membranes to become a technological platform for the investigation and detection of nanoscopic effects and applications in general.…”