A single active nanoelectromechanical tuning fork front-end radio-frequency receiver

Abstract

Nanoelectromechanical systems (NEMS) offer the potential to revolutionize fundamental methods employed for signal processing in today's telecommunication systems, owing to their spectral purity and the prospect of integration with existing technology. In this work we present a novel, front-end receiver topology based on a single device silicon nanoelectromechanical mixer-filter. The operation is demonstrated by using the signal amplification in a field effect transistor (FET) merged into a tuning fork resonator. The combination of both a transistor and a mechanical element into a hybrid unit enables on-chip functionality and performance previously unachievable in silicon. Signal mixing, filtering and demodulation are experimentally demonstrated at very high frequencies (>100 MHz), maintaining a high quality factor of Q = 800 and stable operation at near ambient pressure (0.1 atm) and room temperature (T = 300 K). The results show that, ultimately miniaturized, silicon NEMS can be utilized to realize multi-band, single-chip receiver systems based on NEMS mixer-filter arrays with reduced system complexity and power consumption.

Nanomechanical tuning forks fabricated using focused-ion-beam chemical vapor deposition

“…Although tuning forks have been widely studied, the vibration characteristics of nanomechanical tuning forks are not well understood because only a few have been demonstrated. 12,13 In the work reported in this paper, we investigated the vibration characteristics of nanomechanical tuning forks both theoretically and experimentally. We developed a model of the tuning forks and used it to evaluate the resonant frequencies for the in-phase and antiphase modes.…”

Graphene mechanical oscillators with tunable frequency

“…For comparison, the tunability of commercial very high frequency (VHF) VCOs available from Minicircuits ranges from 0.11% to 106%, with corresponding tunability from 1.5 MHz/V to 161 MHz/V.NEMS hold promise for mechanical RF signal processing, as elements such as filters, modulators, and mixers. In fact, previous work has demonstrated radio receivers based on both carbon nanotubes and Si-NEMS26,27 . Here we demonstrate the use of a graphene VCO to create the complementary structure -a NEMS radio transmitter, which up-converts an audio signal into a frequency-modulated (FM) carrier signal.…”

In-Plane Resonant Nano-Electro-Mechanical Sensors: A Comprehensive Study on Design, Fabrication and Characterization Challenges

“…We have applied a down-mixing technique [40,41] for the RF characterization of the IP R-NEM sensor due to the above mentioned difficulties in the RF characterization of the sensor using a network analyzer. This current technique takes advantage of the intrinsic gain of the integrated JL transistor [42] within the IP R-NEM sensor.…”

“…The lock-in amplifier was used to detect the output current signal, i out , from source. The output current, i out , is defined by [40]: $i_{\text{italicout}}\propto g_{DS}{v}_{in}\frac{\partial i_{DS}}{\partial y}y(\omega )$where g DS is the output conductance, y ( ω ) is the frequency, ω , dependent in-plane displacement. The changes in the drain current, i DS , to the displacement, ∂i DS / ∂y , is calculated by [43]: $\frac{\partial i_{DS}}{\partial y}\approx g_m\frac{C_{eq}^{\prime }}{C_{eq}}{V}_g$where g m is the trransconductance, C eq , is the equivalent gate capacitance, C′ eq is the derivative of C eq .…”