Acoustic properties of co-doped AlN thin films at low temperatures studied by picosecond ultrasonics

Nagakubo, Akira; Arita, Mari; Yokoyama, Tsuyoshi; Matsuda, Satoru; Ueda, Masahiko; Ogi, Hirotsugu; Hirao, Masahiko

doi:10.7567/jjap.54.07hd01

Cited by 12 publications

(14 citation statements)

References 36 publications

(43 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our calculated v P and v S for w-AlN are 10.58 and 6.10 km/s 2 , respectively, which are in good agreement with the values in the literature. , We find that co-doping and Sc doping decrease both the primary and secondary wave velocities as the doping concentration increasesagain due to the decrease in C 33 with the doping concentration. This trend is also observed experimentally for Sc doping and Mg and Hf/Zr co-doping . Li and Ta co-doping shows the lowest velocities, which mainly due to the fact that Ta is the heaviest among our considered elements.…”

Section: Resultssupporting

confidence: 82%

“…This high-throughput/combinatorial approach for Mg and Hf co-doping has demonstrated a promisingly large piezo-response and power generation figure of merit suitable for energy harvesting [17]. Enhancement of piezoelectricity in several other quaternary alloys based on divalent and tetravalent cations in w-AlN (e.g., (Mg,Ti)AlN [18,19], (Mg,Zr)AlN [20,21], and (Zn,Ti)AlN [19]) has also been confirmed experimentally. Moreover, a giant increase of d 33 in w-AlN by co-doping of divalent Mg and pentavalent Nb has been predicted by the first principles calculations [22] and also later confirmed experimentally [23].…”

Section: Introductionmentioning

confidence: 70%

See 1 more Smart Citation

Large Piezoelectric Response and Ferroelectricity in Li and V/Nb/Ta Co-Doped w-AlN

Noor‐A‐Alam

Olszewski

Campanella

et al. 2020

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

Based on density functional theory, we show that Li andX (X=V, Nb and Ta) co-doping in 1Li:1X ratio broadens thecompositional freedom for significant piezoelectric enhancement in w-AlN, promising them to be good alternatives of expensive Sc. Interestingly, these co-doped w-AlN also show quite large spontaneous electric polarization about 0.80 C/m2 with the possibility of ferroelectric polarization switching, opening new possibilities in wurtzite nitrides. Increase in piezoelectric stress constant (e33) with decrease in elastic constant ( C33 ) results enhancement in piezoelectric strain constant ( d33 ), which is desired for improving the performance of resonators for high frequency RF signals. Also, these co-doped w-AlN are potential lead-free piezoelectric materials for energy harvesting and sensors as they improve the longitudinal electromechanical coupling constant (K^2 33), transverse piezoelectric strain constant (d31), and figure of merit for power generation. However, the enhancement in K^2 33 is not as pronounced as that in d33, because co-doping increases the dielectric constant. The longitudinal acoustic wave velocity (7.09 km/s) of Li0.1875Ta0.1875Al0.625N is quite comparable with that of commercially used piezoelectric LiNbO3 or LiTaO3 in special cuts (about 5~7 km/s) despite the fact that the acoustic wave velocities drop with co-doping or Sc concentration. File list (2)download file view on ChemRxiv codoped-AlN.pdf (0.93 MiB) download file view on ChemRxiv codoped-

show abstract

Section: Resultssupporting

confidence: 82%

Section: Introductionmentioning

confidence: 70%

Large Piezoelectric Response and Ferroelectricity in Li and V/Nb/Ta Co-Doped w-AlN

Noor‐A‐Alam

Olszewski

Campanella

et al. 2020

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

show abstract

“…AlN and Ru are hexagonal crystals, therefore, we should compare determined elastic constants with C 33 of each single crystal. AlN shows good agreement with the previous our measurement for a monolayer thin film 49) and other reported values 50,51) as listed in Table II, insisting on the correctness of our GHz-range RUS method for a free-standing film. However, the elastic constant of Ru is about 10% smaller than C 33 values of bulks.…”

supporting

confidence: 90%

GHz-range resonant ultrasound spectroscopy for a free-standing nano film studied by picosecond ultrasonics

Nagakubo

Adachi

Nishihara

et al. 2019

Appl. Phys. Express

Self Cite

View full text Add to dashboard Cite

Progress in the wireless communication requires higher frequency bandpass filters, and the bulk acoustic-wave filter is especially the key device for the GHz-range communication. Its resonance frequencies depend on the elastic constants of individual layers, but it is never straightforward to measure them. In this study, we apply resonant ultrasound spectroscopy to a GHz-range freestanding AlN/Ru/Cr resonator to simultaneously determine the elastic constant of each layer. Using picosecond ultrasonics, we measure free-vibration resonance frequencies up to ∼70 GHz and inversely determine it. The obtained values are reasonable as thin films elasticity, confirming the applicability of the proposed method.

show abstract

“…The experiments 30 parameters of this material but also, and most importantly, in the magnitude of photo-elastic constant. Later the TDBS experiments were realized with other combinations of transparent materials such as various transparent layers deposited on silicon 31,70,74,78 , GaSb-GaAs heterostructures 72 , ZnO and SiO 2 deposited on GaAs, 35 the vacuole of a cell deposited on a thin polyethyleneimine film 79 and even microcapsules composed of polymer shell encapsulating a liquid core 80,81 . The TDBS with a variable probe wavelength were conducted in GaAs 72,73 .…”

Section: Applications Of Time-domain Brillouin Scattering For Nanosca...mentioning

confidence: 99%

Advances in applications of time-domain Brillouin scattering for nanoscale imaging

Gusev

Ruello

2018

Applied Physics Reviews

View full text Add to dashboard Cite

Time-domain Brillouin scattering is an all-optical experimental technique based on ultrafast lasers applied for generation and detection of coherent acoustic pulses on time durations of picoseconds and length scales of nanometers. In transparent materials scattering of the probe laser beam by the coherent phonons permits imaging of sample inhomogeneity. The transient optical reflectivity of the sample recorded by the probe beam as the acoustic nanopulse propagates in space contains information on the acoustical, optical, and acousto-optical parameters of the material under study. The experimental method is based on a heterodyning where weak light pulses scattered by the coherent acoustic phonons interfere at the photodetector with probe light pulses of significantly higher amplitude reflected from various interfaces of the sample. The time-domain Brillouin scattering imaging is based on Brillouin scattering and has the potential to provide all the information that researchers in material science, physics, chemistry, biology etc., get with classic frequency-domain Brillouin scattering of light. It can be viewed as a replacement for Brillouin scattering and Brillouin microscopy in all investigations where nanoscale spatial resolution is either required or advantageous. Here we review applications of time-domain Brillouin scattering for imaging of nanoporous films, ion-implanted semiconductors and dielectrics, texture in polycrystalline materials and inside vegetable and animal cells, and for monitoring the transformation of 2nanosound caused by nonlinearity and focusing. We also discuss the perspectives and the challenges for the future.I.

show abstract

Acoustic properties of co-doped AlN thin films at low temperatures studied by picosecond ultrasonics

Cited by 12 publications

References 36 publications

Large Piezoelectric Response and Ferroelectricity in Li and V/Nb/Ta Co-Doped w-AlN

Large Piezoelectric Response and Ferroelectricity in Li and V/Nb/Ta Co-Doped w-AlN

GHz-range resonant ultrasound spectroscopy for a free-standing nano film studied by picosecond ultrasonics

Advances in applications of time-domain Brillouin scattering for nanoscale imaging

Contact Info

Product

Resources

About