Matteo Rinaldi

Ultra-Thin-Film AlN Contour-Mode Resonators for Sensing Applications

Matteo Rinaldi et al. — Thu, 30 Sep 2010 07:28:33 PDT

This paper reports on the design and experimental verification of a new class of ultra-thin-film (250 nm) aluminum nitride (AlN) microelectromechanical system (MEMS) contour mode resonators (CMRs) suitable for the fabrication of ultra-sensitive gravimetric sensors. The device thickness was opportunely scaled in order to increase the mass sensitivity, while keeping a constant frequency of operation. In this first demonstration the resonance frequency of the device was set to 178 MHz and a mass sensitivity as high as 38.96 KHz⋅μm2/fg was attained. This device demonstrates the unique capability of the CMR-S technology to decouple resonance frequency from mass sensitivity.

ss-DNA Functionalized Ultra-Thin-Film AlN Contour-Mode Resonators with Self-Sustained Oscillator for Volatile Organic Chemical Detection

Matteo Rinaldi et al. — Wed, 29 Sep 2010 19:20:34 PDT

This paper reports on the design and experimental verification of a new class of nanoscale gravimetric sensors based on ultra-thin-film AlN Contour-Mode Resonant Sensor (CMR-S) functionalized with ss-DNA and connected to a chip-based self-sustaining oscillator loop (fabricated in the ON Semiconductor 0.5 μm CMOS process) for direct frequency read-out. The 220 MHz oscillator based on the ultra-thin AlN CMR-S exhibits an Allan Variance of ∼20 Hz for 100 ms gate time. The sensor affinity for the adsorption of volatile organic chemicals such as 2,6 dinitroluene (DNT, a simulant for explosive vapors) is enhanced by functionalizing the top gold electrode of the device with a thiol-terminated single stranded DNA sequence (Thiol - 5’ CTT CTG TCT TGA TGT TTG TCA AAC 3’) enabling the detection of concentrations as low as 1.5 part per billion (ppb).

GHz Range Nanoscaled AlN Contour-Mode Resonant Sensors (CMR-S) with Self-Sustained CMOS Oscillator

Matteo Rinaldi et al. — Wed, 29 Sep 2010 19:06:01 PDT

This paper reports on the design and experimental verification of a new class of nanoscaled AlN Contour-Mode Resonant Sensors (CMR-S) for the detection of volatile organic chemicals (VOC) operating at frequencies above 1 GHz and connected to a chip-based CMOS oscillator circuit for direct frequency read-out. This work shows that by scaling the CMR-S to 250 nm in thickness and by operating at high frequencies (1 GHz) a limit of detection of ~35 zg/µm2 and a fast response time (<1 >ms) can be attained. In addition, the capability to detect concentrations of volatile organic compounds such as 2,6 dinitroluene (DNT) as low as 1.5 ppb (4.7 ag/µm2) is experimentally verified.

Power Handling and Related Frequency Scaling Advantages in Piezoelectric AlN Contour-Mode MEMS Resonators

Chengjie Zuo et al. — Wed, 29 Sep 2010 19:06:00 PDT

This paper reports on the analytical modeling and experimental verification of the mechanically-limited power handling and nonlinearity in piezoelectric aluminum nitride (AlN) contour-mode resonators (CMR) having different electrode configurations (thickness field excitation, lateral field excitation, one-port and two-port configurations) and operating at different frequencies (177-3047 MHz). Despite its simplicity, the one-dimensional analytical model fits the experimental behavior of AlN CMRs in terms of power handling capabilities. The model and experiment also confirm the advantage of scaling (i.e. miniaturizing) the AlN CMRs to higher frequencies at which higher critical power density can be more easily attained up to values in excess of 10 μW/μm3.

Ultra-Thin Super High Frequency Two-Port ALN Contour-Mode Resonators and Filters

Matteo Rinaldi et al. — Wed, 29 Sep 2010 19:06:00 PDT

This paper reports on the demonstration of a new class of ultra-thin (250 nm thick) super high frequency (SHF) AlN piezoelectric two-port resonators and filters. A thickness field excitation scheme was employed to excite a higher order contour extensional mode of vibration in an AlN nano plate (250 nm thick) above 3 GHz and synthesize a 1.96 GHz narrow-bandwidth channel-select filter. The devices of this work are able to operate over a frequency range from 1.9 to 3.5 GHz and are employed to synthesize the highest frequency MEMS filter based on electrically self-coupled AlN contour-mode resonators. Very narrow bandwidth (~ 0.35%) and high off-band rejection (~ 35 dB) were achieved at an operating frequency of 1.96 GHz. This first prototype showed insertion loss of 11 dB, which can be improved to few dB if parasitic elements are eliminated or device capacitance is increased.

Super-High-Frequency Two-Port AlN Contour-Mode Resonators for RF Applications

Matteo Rinaldi et al. — Fri, 08 Jan 2010 15:38:07 PST

This paper reports on the design and experimental verification of a new class of thin-film (250 nm) super-high-frequency laterally-vibrating piezoelectric microelectromechanical (MEMS) resonators suitable for the fabrication of narrow-band MEMS filters operating at frequencies above 3 GHz. The device dimensions have been opportunely scaled both in the lateral and vertical dimensions to excite a contour-extensional mode of vibration in nanofeatures of an ultra-thin (250 nm) AlN film. In this first demonstration, 2-port resonators vibrating up to 4.5 GHz have been fabricated on the same die and attained electromechanical coupling, kt2, in excess of 1.5%. These devices are employed to synthesize the highest frequency MEMS filter (3.7 GHz) based on AlN contour-mode resonator technology ever reported.

AlN Contour-Mode Resonators for Narrow-Band Filters above 3 GHz

Matteo Rinaldi et al. — Fri, 24 Jul 2009 12:42:00 PDT

This paper reports on the design and experimental verification of a new class of thin-film (250 nm) Super High Frequency (SHF) laterally-vibrating piezoelectric microelectromechanical (MEMS) resonators suitable for the fabrication of narrow-band MEMS filters operating at frequencies above 3 GHz. The device dimensions have been opportunely scaled both in the lateral and vertical dimensions in order to excite a contour-extensional mode of vibration in nano features of an ultra-thin (250 nm) Aluminum Nitride (AlN) film. In this first demonstration two-port resonators vibrating up to 4.5 GHz were fabricated on the same die and attained electromechanical coupling, kt2, in excess of 1.5 %. These devices were employed to synthesize the highest frequency ever reported MEMS filter (3.7 GHz) based on AlN contour-mode resonator (CMR) technology.

Ultra-Thin Super High Frequency Two-Port AlN Contour-Mode Resonators and Filters

Matteo Rinaldi et al. — Fri, 24 Jul 2009 12:41:59 PDT

This paper reports on the demonstration of a new class of ultra-thin (250 nm thick) Super High Frequency (SHF) AlN piezoelectric two-port resonators and filters. A thickness field excitation scheme was employed to excite a higher order contour extensional mode of vibration in an AlN nano plate (250 nm thick) above 3 GHz and synthesize a 1.96 GHz narrow-bandwidth channel-select filter. The devices of this work are able to operate over a frequency range from 1.9 to 3.5 GHz and are employed to synthesize the highest frequency MEMS filter based on electrically self-coupled AlN contour-mode resonators. Very narrow bandwidth (~ 0.35%) and high off-band rejection (~ 35 dB) were achieved at an operating frequency of 1.96 GHz. This first prototype showed insertion loss of 11 dB, which can be improved to few dB if parasitic elements are eliminated or device capacitance is increased.

DNA-Decorated Carbon Nanotubes as Sensitive Layer for AlN Contour-Mode Resonant-MEMS Gravimetric Sensor

Chiara Zuniga et al. — Thu, 18 Jun 2009 08:19:46 PDT

In this work a nano-enabled gravimetric chemical sensor prototype based on single-stranded DNA (ss-DNA) decorated single-walled carbon nanotubes (SWNT) as nano-functionalization layer for Aluminun Nitride (AIN) contour-mode resonant-MEMS gravimetric sensors has been demonstrated. Two resonators fabricated on the same silicon chip and operating at different resonance frequencies, 287 and 450 MHz, were functionalized with this novel bio-coating layer to experimentally prove the capability of two distinct single strands of DNA bound to SWNT to enhance differently the adsorption of volatile organic compounds such as dinitroluene (DNT, simulant for explosive vapor) and dymethyl-methylphosphonate (DMMP, a simulant for nerve agent sarin). The introduction of this bio-coating layer addresses the major drawbacks of recovery time (50% recovery in less than 29 seconds has been achieved) and lack of selectivity associated with gas sensor based on polymers and pristine carbon nanotube functionalization layers.

Nanoenabled microelectromechanical sensor for volatile organic chemical detection

Chiara Zuniga et al. — Wed, 10 Jun 2009 07:58:54 PDT

A nanoenabled gravimetric chemical sensor prototype based on the large scale integration of single-stranded DNA (ss-DNA) decorated single-walled carbon nanotubes (SWNTs) as nanofunctionalization layer for aluminum nitride contour-mode resonant microelectromechanical (MEM) gravimetric sensors has been demonstrated. The capability of two distinct single strands of DNA bound to SWNTs to enhance differently the adsorption of volatile organic compounds such as dinitroluene (simulant for explosive vapor) and dymethyl-methylphosphonate (simulant for nerve agent sarin) has been verified experimentally. Different levels of sensitivity (17.3 and 28 KHz µm^2/fg) due to separate frequencies of operation (287 and 450 MHz) on the same die have also been shown to prove the large dynamic range of sensitivity attainable with the sensor. The adsorption process in the ss-DNA decorated SWNTs does not occur in the bulk of the material, but solely involves the surface, which permits to achieve 50% recovery in less than 29 s.

5-10 GHz AlN Contour-Mode Nanoelectromechanical Resonators

Matteo Rinaldi et al. — Thu, 04 Jun 2009 07:04:18 PDT

This paper reports on the design and experimental verification of Super High Frequency (SHF) laterally vibrating NanoElctroMechanical (NEMS) resonators. For the first time, AlN piezoelectric nanoresonators with multiple frequencies of operation ranging between 5 and 10 GHz have been fabricated on the same chip and attained the highest f-Q product (4.6E12 Hz) ever reported in AlN contour-mode devices. These piezoelectric NEMS resonators are the first of their class to demonstrate on-chip sensing and actuation of nanostructures without the need of cumbersome or power consuming excitation and readout systems. Effective piezoelectric activity has been demonstrated in thin AlN films having vertical and lateral features in the range of 250 nm.

Gravimetric chemical sensor based on the direct integration of SWNTS on ALN Contour-Mode MEMS resonators

Matteo Rinaldi et al. — Mon, 17 Nov 2008 10:41:04 PST

This paper reports on the first demonstration of a gravimetric chemical sensor based on direct integration of Single Wall Carbon Nanotubes (SWNTs) grown by Chemical Vapor Deposition (CVD) on AlN Contour-Mode MicroElectroMechanical (MEMS) resonators. In this first prototype the ability of SWNTs to readily adsorb volatile organic chemicals has been combined with the capability of AlN Contour-Mode MEMS resonator to provide for different levels of sensitivity due to separate frequencies of operation on the same die. Two devices with resonance frequencies of 287 MHz and 442 MHz have been exposed to different concentrations of DMMP in the range from 80 to 800 ppm. Values of mass sensitivity equal to 1.8 KHz/pg and 2.65 KHz/pg respectively have been measured.