Online Condition Monitoring Methodology for Power Electronics Package Reliability Assessment

This article introduces an online condition monitoring strategy that utilizes a transient heat pulse to detect package thermal performance degradation. The metric employed is the temperature-dependent transient thermal impedance "Zth(t, Tamb)."The proposed methodology offers quantitative insights into package thermal performance degradation...

Light transmittance in human atrial tissue and transthoracic illumination in rats support translatability of optogenetic cardioversion of atrial fibrillation

Background: Optogenetics could offer a solution to the current lack of an ambulatory method for the rapid automated cardioversion of atrial fibrillation (AF), but key translational aspects remain to be studied. Objective: To investigate whether optogenetic cardioversion of AF is effective in the aged heart and whether sufficient light...

Ultrasound-Guided Optogenetic Gene Delivery for Shock-Free Ventricular Rhythm Restoration

Optical ventricular cardioversion by local optogenetic targeting and LED implantation in a cardiomyopathic rat model

AIMS: Ventricular tachyarrhythmias (VTs) are common in the pathologically remodelled heart. These arrhythmias can be lethal, necessitating acute treatment like electrical cardioversion to restore normal rhythm. Recently, it has been proposed that cardioversion may also be realized via optically controlled generation of bioelectricity by the...

Antenna-in-Package (AiP) Using Through-Polymer Vias (TPVs) for a 122-GHz Radar Chip

High-performance IC-to-antenna interconnection is one of the key enablers for the mass production of high-end millimeter wave (mmW) radar systems above 100 GHz. In this work, a radar system with an on-package antenna array working at 122 GHz is presented. The antenna is placed on top of the molded package and the antenna-to-chip interconnection...

Simulation for stability of a beam-mass based high-resolution MEMS gravimeter

In this paper, stability and mechanistic simulations for a four-beam-mass-based MEMS gravimeter were conducted, and guidelines for the gravimeter design were proposed. Based on a prototyped MEMS device, the nonlinear finite element model was validated first against the experimental results. Then, we demonstrated three different scenarios in...

Vertically-Aligned Multi-Walled Carbon Nano Tube Pillars with Various Diameters under Compression: Pristine and NbTiN Coated

In this paper, the compressive stress of pristine and coated vertically-aligned (VA) multi-walled (MW) carbon nanotube (CNT) pillars were investigated using flat-punch nano-indentation. VA-MWCNT pillars of various diameters (30–150 µm) grown by low-pressure chemical vapor deposition on silicon wafer. A conformal brittle coating of niobium...

High-resolution MEMS inertial sensor combining large-displacement buckling behaviour with integrated capacitive readout

Commercially available gravimeters and seismometers can be used for measuring Earth’s acceleration at resolution levels in the order of ng∕Hz (where g represents earth’s gravity) but they are typically high-cost and bulky. In this work the design of a bulk micromachined MEMS device exploiting non-linear buckling behaviour is described, aiming...

Effects of Conformal Nanoscale Coatings on Thermal Performance of Vertically Aligned Carbon Nanotubes

The high aspect ratio and the porous nature of spatially oriented forest-like carbon nanotube (CNT) structures represent a unique opportunity to engineer a novel class of nanoscale assemblies. By combining CNTs and conformal coatings, a 3D lightweight scaffold with tailored behavior can be achieved. The effect of nanoscale coatings, aluminum...

Stretchable Binary Fresnel Lens for Focus Tuning

This paper presents a tuneable binary amplitude Fresnel lens produced by wafer-level microfabrication. The Fresnel lens is fabricated by encapsulating lithographically defined vertically aligned carbon nanotube (CNT) bundles inside a polydimethyl-siloxane (PDMS) layer. The composite lens material combines the excellent optical absorption...

Thermal characterization of carbon nanotube foam using MEMS microhotplates and thermographic analysis

Thermal material properties play a fundamental role in the thermal management of microelectronic systems. The porous nature of carbon nanotube (CNT) arrays results in a very high surface area to volume ratio, which makes the material attractive for surface driven heat transfer mechanisms. Here, we report on the heat transfer performance of...

Tailoring the Mechanical Properties of High-Aspect-Ratio Carbon Nanotube Arrays using Amorphous Silicon Carbide Coatings

The porous nature of carbon nanotube (CNT) arrays allows for the unique opportunity to tailor their mechanical response by the infiltration and deposition of nanoscale conformal coatings. Here, we fabricate novel photo-lithographically defined CNT pillars that are conformally coated with amorphous silicon carbide (a-SiC) to strengthen the...

Establishment of the coarse grained parameters for epoxy-copper interfacial separation

Atomistic coarse grained parameters were calculated from a non-equilibrium molecular dynamics simulation of the separation of an epoxy-copper interface. The methodology to determine the interaction energy and the equilibrium distance between the interfacial materials at a minimum energy is established. The traction-displacement relations of the...