Physics Commons^™

Fabrication Of Robust Superconducting Granular Aluminium/Palladium Bilayer Microbolometers With Sub-Nanosecond Response, Thomas E. Wilson

Physics Faculty Research

We provide a convenient recipe for fabricating reliable superconducting microbolometers as acoustic phonon detectors with sub-nanosecond response, using imagereversal optical lithography and dc-magnetron sputtering, and our recipe requires no chemical or plasma etching. Our approach solves the traditional problem for granular aluminium bolometers of unreliable (i.e., non-Ohmic) electrical contacts by sequentially sputtering the granular aluminium film and then a palladium capping layer. We use dc calibration data, the method of Danilchenko et al. [1], and direct nanosecond-pulsed photoexcitation to obtain the microbolometer’s characteristic current, thermal conductance, characteristic relaxation time, and heat capacity. We also demonstrate the use of the deconvolution …

The Fabrication And Characterization Of Granular Aluminium/Palladium Bilayer Microbolometers, Thomas E. Wilson

Physics Faculty Research

Superconducting granular aluminium/palladium bilayer microbolometers with subnanosecond response can be easily fabricated using an all lift-off process with image-reversal lithography. The palladium capping layer allows for convenient and reproducible Ohmic contacts to be made to the device. We report their fabrication, resistance–current calibration, responsivity and response time. Finally, a deconvolution algorithm is used to improve the time resolution to approximately 1 ns while obtaining the incident photon and phonon fluxes in both direct photoexcitation and phonon heat pulse experiments.

Accessibility Of Home Blood Pressure Monitors For Blind And Visually Impaired People, Mark M. Uslan, Darren M. Burton, Thomas E. Wilson, Steven Taylor, Bruce S. Chertow, Jack E. Terry

Physics Faculty Research

Background: The prevalence of hypertension comorbid with diabetes is a significant health care issue. Use of the home blood pressure monitor (HBPM) for aiding in the control of hypertension is noteworthy because of benefits that accrue from following a home measurement regimen. To be usable by blind and visually impaired patients, HBPMs must have speech output to convey all screen information, an easily readable visual display, identifiable controls that are easy to use, and an accessible user manual.

Methods: Data on the physical aspects and the features and functions of nine Food and Drug Administration-approved HBPMs (eight of which were …

Contact Printed Co/Insulator/Co Molecular Junctions, Xiaojuan Fan, David L. Rogow, Claudia H. Swanson, Akhilesh Tripathi, Scott R. J. Oliver

Physics Faculty Research

The authors report the contact printing of a Au/Co double layer (total thickness ∼20–40nm) onto a self-assembled monolayer surface to form molecular junctions under ambient conditions. The feature size ranges from 50×50μm² to 2×2 mm². Grazing incident x-ray diffraction of the multilayer junction shows all expected Au peaks, while elemental Co was confirmed by energy dispersive spectroscopy. Film thickness, roughness, and density were characterized by x-ray reflectivity. I-V measurements show a prominent hysteresis, likely associated with charge trapping at the metal-organic interface, not an intrinsic feature of alkanedithiol molecules.