Recent advances in harsh environment acoustic wave sensors for contemporary applications

Cunha, M. Pereira da; Lad, Robert J.; Moonlight, T.; Moulzolf, Scott C.; Canabal, A.; Behanan, R.; Davulis, P.; Frankel, D.; Bernhardt, G.; Pollard, T.B.; McCann, Donald F.

doi:10.1109/icsens.2011.6126948

Cited by 23 publications

(18 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In reference [19], anelastic properties of LGS and LGT have been studied for high temperature operation, targeting frequency control and mass deposition devices. Langasite crystals and devices have been exposed to abrupt shocks in temperature and pressure, and to turbine engine vibration environments without compromising the material integrity [20] [21].…”

Section: A Piezoelectric Crystals and Films For Harsh Environmentsmentioning

confidence: 99%

Wireless sensing in hostile environments

Cunha

2013

2013 IEEE International Ultrasonics Symposium (IUS)

View full text Add to dashboard Cite

Microwave acoustic devices have long been shown to provide sensitive platforms for physical and gas sensors. Piezoelectric substrates introduced over the past two decades, such as the langasite (LGS) family of crystals, gallium orthophosphate, and aluminum nitride have enabled the exploration of microwave acoustics sensing at temperatures above 500°C. However the ability of the substrate to withstand high temperatures is only one of the requirements for sensor operation in harsh environments. Other prerequisites are: the development of stable high-temperature device electrodes; appropriate packaging; and resilience of the entire system to thermal shock and thermal cycling. In this paper, the wireless operation of microwave acoustic wave sensors in harsh environments is reviewed, and recent achievements are highlighted. Particular focus is given to surface acoustic wave (SAW) sensor technology because it has the advantage of being wireless, battery-free, and allows interrogation of arrays of multiple devices. During the last decade, wireless hostile environment microwave acoustic sensors that can detect gases and monitor temperature and pressure have transitioned from laboratory proof-of-concept to commercial devices and systems. Recent accomplishments in thin film technology and packaging are extending the technology to even higher temperatures, beyond 1000°C. These technological advances are enabling wireless microwave acoustic sensor applications in hostile environments including power plants, turbine engines, oil/gas refineries, and high temperature industrial processing.

show abstract

Section: A Piezoelectric Crystals and Films For Harsh Environmentsmentioning

confidence: 99%

Wireless sensing in hostile environments

Cunha

2013

2013 IEEE International Ultrasonics Symposium (IUS)

View full text Add to dashboard Cite

show abstract

“…Typical thin-film (~100 to 200 nm) platinum electrodes are prone to agglomeration and dewetting, leading to failure at elevated temperatures [1][2][3] and many mechanisms are responsible for this behavior [4]. In an effort to extend the operational temperature of LGS SAW devices for wireless applications in harsh environments, nanocomposite films have been developed at UMaine, such as Pt-Rh/ZrO 2 [3,[5][6] and more recently Pt-Rh/HfO 2 [7][8]. These films inhibit the dewetting process when compared to pure Pt films of the same thickness, thus extending the SAW device temperature of operation beyond 900C.…”

Section: Introductionmentioning

confidence: 99%

Capacitively coupled IDT for high temperature SAW devices

Moulzolf

Behanan

Pollard

et al. 2013

2013 IEEE International Ultrasonics Symposium (IUS)

Self Cite

View full text Add to dashboard Cite

Harsh environment surface acoustic wave (SAW) sensors are being researched and developed jointly by the University of Maine (UMaine) and Environetix Technologies Corp. for wireless and wired sensor applications, such as those found in gas turbines and power plant combustors. One goal of this work is to extend the operational temperature range of SAW sensors above 1000C, potentially up to near the melting point of piezoelectric langasite crystals at 1400C. To achieve stable performance at 1000  C and above, UMaine has developed nanocomposite thin film electrode materials, such as PtRh/HfO 2 , and protecting capping layers, such as SiAlON and Al 2 O 3 . However, these protective top layers, which aid in extending the life of the electrodes, are electrical insulators that prevent direct bonding to the electrodes. The UMaine team also found evidence of accelerated thin-film degradation close to the SAW interdigital transducer (IDT) bond pad welds at these extreme temperatures. This paper introduces a high temperature capacitive approach to electrically couple to the IDT, thus allowing electrical access to the SAW device. The capacitive coupling approach also avoids premature failure of the nanocomposite film caused by interdiffusion between the bond wires and the SAW IDT bond pads. The technique has been successfully implemented and SAW device operation at 1000C has been achieved.

show abstract

“…However, thanks to recent developments, SAW properties can now be easier characterized up to 900°C [2][3]. The change of SAW velocity with temperature depends directly on the TC1 and TC2 coefficients.…”

Section: Introductionmentioning

confidence: 99%

An optimized set of temperature coefficients for LGS

Nicolay

Aubert

2013

2013 IEEE International Ultrasonics Symposium (IUS)

View full text Add to dashboard Cite

LGS is a promising material for SAW applications at high temperature. However, the temperature coefficients of LGS material constants are not accurate enough to perform reliable simulations above 300°C. In the first part of the paper, we describe a new possible way to derive these coefficients in a wider temperature range. The calculated coefficients allow for accurate predictions up to at least 800°C. In the second part, a deeper analysis of the algorithm outputs demonstrates some of its main limitations. Possible solutions are described to predict then improve the accuracy of the optimized coefficients values.

show abstract

Recent advances in harsh environment acoustic wave sensors for contemporary applications

Cited by 23 publications

References 13 publications

Wireless sensing in hostile environments

Wireless sensing in hostile environments

Capacitively coupled IDT for high temperature SAW devices

An optimized set of temperature coefficients for LGS

Contact Info

Product

Resources

About