This paper presents a sub–0.1-mm 3 , fully integrated, injectable ultrasonic wireless device for biomedical temperature sensing.

Accurate monitoring of physiological temperature is important for many biomedical applications, including core body temperature, detecting tissue pathologies, and evaluating surgical procedures involving thermal treatment such as hyperthermia therapy ablation. Many these applications can benefit from replacing external probes with injectable wireless devices. Here we present a device real-time in vivo that relies on "chip-as-system" integration. With an on-chip piezoelectric transducer...

Abstract Ultrasound imaging provides the means for non-invasive real-time diagnostics of internal structure soft tissue in living organisms. However, majority commercially available ultrasonic transducers have rigid interfaces which cannot conform to highly-curved surfaces. These geometric limitations can introduce a signal-quenching air gap certain topographies, rendering accurate difficult or impractical. Here, we demonstrate 256-element flexible two-dimensional (2D) ultrasound...

Emerging non-imaging ultrasound applications, such as ultrasonic wireless power delivery to implantable devices and neuromodulation, require wearable form factors, millisecond-range pulse durations focal spot diameters approaching 100 μm with electronic control of its three-dimensional location. None these are compatible typical handheld linear array imaging probes. In this work, we present a 4 mm × 5 2D phased transmitter integrated piezoelectric transducers on complementary...

Characterizing the human head as a propagation medium is vital for design of both on-body and implanted antennas radio-frequency sensors. The following problem has been addressed: find best path through brain given receiver position-on top sinus cavity. Two parameters, transmitter position radiating frequency, should be optimized simultaneously such that 1) longest; 2) received power maximized. To solve this problem, we have performed systematic comprehensive study electromagnetic fields...

There is growing interest in integrating piezoelectric materials with complementary metal-oxide-semiconductor (CMOS) technology to enable expanded applications. A promising material for ultrasound transducer applications poly(vinylidene fluoride) (PVDF), a polymer. One of the challenges PVDF that its properties can deteriorate when exposed temperatures excess 70 °C extended periods time during fabrication. Here, we report on effects both shortening annealing times and providing this heating...

Abstract Modern clinical practice benefits significantly from imaging technologies and much effort is directed toward making this more informative through the addition of contrast agents or reporters. Here, we report design a battery-less integrated circuit mote acting as an electronic reporter during medical ultrasound imaging. When implanted within field-of-view brightness-mode (B-mode) imager, transmits information its location backscattered acoustic energy which captured image itself. We...

We present the development of micro-fabrication techniques achieving monolithic integration micron-scale piezoelectric ultrasonic transducers in both polyvinylidene difluoride (PVDF) and lead zirconate titanate (PZT) with complementary metal-oxide-semiconductor (CMOS) integrated circuits (ICs). PVDF-CMOS is driven by applications energy harvesting data telemetry for medical implants, while PZT-CMOS applied to high-resolution two-dimensional (2D) ultrasound imaging. Both these benefit from...

Dielectric properties of Cerebral Spinal Fluid (CSF) at microwave frequencies correlate with a higher level glucose or protein observed certain diseases, including early stages Alzheimer's disease. In this study, simulation in vivo monitoring dielectric using small antennas precisely positioned around the human head is made. We use realistic mesh model and organs obtained by fine segmentation Visible Human Project® data. An accurate source coincident phase centers employed underlying Finite...

Abstract This article describes the design of a compact ferrite loaded UHF sleeve monopole antenna covering 225–450 MHz that is colocated with GPS annular ring microstrip antennas on top handset. provides both communications and navigational capabilities to user intended for military commercial applications. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2513–2516, 2012; View this online at wileyonlinelibrary.com. DOI 10.1002/mop.27102

The unique flexible and piezoelectric properties of polyvinylidene fluoride (PVDF) films would allow for new applications integrated bioelectronic devices. use these has been precluded by the difficulty in machining them into small, discrete features without damaging material. etching PVDF means a 193 nm excimer laser is explored characterized. Etch rates are shown common fluence values, along with images quality cuts to provide reader an understanding compromise between etch rate edge...

Characterizing the human head as a propagation medium is vital for design of both on-body and implanted antennas radio-frequency sensors. The following problem has been addressed: find best path through brain given receiver position - on top sinus cavity. Two parameters: transmitter radiating frequency should be optimized simultaneously such that (i) longest; (ii) received power maximized. To solve this problem, we have performed systematic comprehensive study electromagnetic fields excited...

Characterizing the human head as a propagation medium is useful for remotely observing changes in material properties of body. In this study, extensive simulations were performed using Finite Element Method (FEM) to examine fields excited by continuous wave. A custom mesh was developed include brain, skull, and cerebrospinal fluid (CSF). Small orthogonal coil antennas systematically placed generate highly directive beam through head. These beams can be directed into mouth where signal...