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High frequency (∼30MHz and ∼80MHz) focusing ultrasound transducers were fabricated using a PMN-0.28PT single crystal by a mechanical dimpling technique. The dimpled single crystal was used as an active element for the focusing transducer. Compared with a plane transducer, the focusing transducer fabricated with a dimpled active element exhibits much broader(More)
Lead magnesium niobate-lead titanate single crystal 0.72Pb(Mg(13)Nb(23))O(3)-0.28PbTiO(3) (abbreviated as PMN-PT) was used to fabricate high performance ultrasonic phased-array transducer as it exhibited excellent piezoelectric properties. In this paper, we focus on the design and fabrication of a low-loss and wide-band transducer for medical imaging(More)
The paper describes the design, fabrication, and measurements of a high-frequency ultrasound kerfless linear array prepared from hydrothermal lead zirconate titanate (PZT) thick film. The 15-μm hydrothermal PZT thick film with an area of 1 × 1 cm, obtained through a self-separation process from Ti substrate, was used to fabricate a 32-element 100-MHz(More)
Visualization of the blood vessels can provide valuable morphological information for diagnosis and therapy strategies for cardiovascular disease. Intravascular ultrasound (IVUS) is able to delineate internal structures of vessel wall with fine spatial resolution. However, the developed IVUS is insufficient to identify the fibrous cap thickness and tissue(More)
In this work, a novel high-frequency ultrasonic transducer structure is realized by using PMNPT-on-silicon technology and silicon micromachining. To prepare the single crystalline PMNPT-on-silicon wafers, a hybrid processing method involving wafer bonding, mechanical lapping and wet chemical thinning is successfully developed. In the transducer structure,(More)
Amorphous black phosphorus (a-BP) ultrathin films are deposited by pulsed laser deposition. a-BP field-effect trans-istors, exhibiting high carrier mobility and moderate on/off current ratio, are demonstrated. Thickness dependence of the bandgap, mobility, and on/off ratio are observed. These results offer not only a new nanoscale member in the BP family,(More)
A ∼5MHz focusing PMN-PT single crystal ultrasound transducer has been fabricated utilizing a mechanical dimpling technique, where the dimpled crystal wafer was used as an active element of the focusing transducer. For the dimpled focusing transducer, the effective electromechanical coupling coefficient was enhanced significantly from 0.42 to 0.56. The(More)
In this paper, 0.7Pb(Mg(¹/₃)Nb(²/₃)O₃-0.3PbTiO₃ (PMN-PT) single crystal/epoxy 1/3 composite was used as the active material of the endoscopic ultrasonic radial array transducer, because this composite exhibited ultrahigh electromechanical coupling coefficient (k(t) = 0.81%), very low mechanical quality factor (Q(m) = 11) and relatively low acoustic(More)
Relaxor-based ferroelectric single crystals Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) have drawn much attention in the ferroelectric field because of their excellent piezoelectric properties and high electromechanical coupling coefficients (d33~2000 pC/N, kt~60%) near the morphotropic phase boundary (MPB). Ternary Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3(More)
In this paper, 1-3 composites based on Pb(In(1∕2)Nb(1∕2))-Pb(Mg(1∕3)Nb(2∕3))-PbTiO(3) (PIMNT) single crystal and high-temperature epoxy were fabricated with various volume fractions of PIMNT single crystal ranging from 0.4 to 0.9. The electrical properties were studied as functions of PIMNT volume fraction and temperature, and it revealed that the nature of(More)