245 research outputs found
MEMS Technology for Biomedical Imaging Applications
Biomedical imaging is the key technique and process to create informative images of the human body or other organic structures for clinical purposes or medical science. Micro-electro-mechanical systems (MEMS) technology has demonstrated enormous potential in biomedical imaging applications due to its outstanding advantages of, for instance, miniaturization, high speed, higher resolution, and convenience of batch fabrication. There are many advancements and breakthroughs developing in the academic community, and there are a few challenges raised accordingly upon the designs, structures, fabrication, integration, and applications of MEMS for all kinds of biomedical imaging. This Special Issue aims to collate and showcase research papers, short commutations, perspectives, and insightful review articles from esteemed colleagues that demonstrate: (1) original works on the topic of MEMS components or devices based on various kinds of mechanisms for biomedical imaging; and (2) new developments and potentials of applying MEMS technology of any kind in biomedical imaging. The objective of this special session is to provide insightful information regarding the technological advancements for the researchers in the community
Development of a Macro-Pixel sensor for the Phase-2 Upgrade of the CMS experiment
No description available (migrated from EKP Invenio record 49080
NASA Tech Briefs, October 2001
Topics include: special coverage section on composites and plastics, electronic components and systems, software, mechanics, physical sciences, information sciences, book and reports, and a special sections of Photonics Tech Briefs and Motion Control Tech Briefs
Optoelectronic devices and packaging for information photonics
This thesis studies optoelectronic devices and the integration of these components onto
optoelectronic multi chip modules (OE-MCMs) using a combination of packaging
techniques. For this project, (1×12) array photodetectors were developed using PIN
diodes with a GaAs/AlGaAs strained layer structure. The devices had a pitch of 250μm,
operated at a wavelength of 850nm. Optical characterisation experiments of two types
of detector arrays (shoe and ring) were successfully performed. Overall, the shoe
devices achieved more consistent results in comparison with ring diodes, i.e. lower dark
current and series resistance values. A decision was made to choose the shoe design for
implementation into the high speed systems demonstrator. The (1x12) VCSEL array
devices were the optical sources used in my research. This was an identical array at
250μm pitch configuration used in order to match the photodetector array. These
devices had a wavelength of 850nm. Optoelectronic testing of the VCSEL was
successfully conducted, which provided good beam profile analysis and I-V-P
measurements of the VCSEL array. This was then implemented into a simple
demonstrator system, where eye diagrams examined the systems performance and
characteristics of the full system and showed positive results.
An explanation was given of the following optoelectronic bonding techniques: Wire
bonding and flip chip bonding with its associated technologies, i.e. Solder, gold stud
bump and ACF. Also, technologies, such as ultrasonic flip chip bonding and gold
micro-post technology were looked into and discussed. Experimental work
implementing these methods on packaging the optoelectronic devices was successfully
conducted and described in detail. Packaging of the optoelectronic devices onto the OEMCM
was successfully performed. Electrical tests were successfully carried out on the
flip chip bonded VCSEL and Photodetector arrays. These results verified that the
devices attached on the MCM achieved good electrical performance and reliable
bonding. Finally, preliminary testing was conducted on the fully assembled OE-MCMs.
The aim was to initially power up the mixed signal chip (VCSEL driver), and then
observe the VCSEL output
The development of microfabricated ion traps towards quantum information and simulation
Trapped ions within Paul traps have shown to be a promising architecture in the realisation
of a quantum information processor together with the ability of providing quantum
simulations. Linear Paul traps have demonstrated long coherence times with ions being
well isolated from the environment, single and multi-qubit gates and the high fidelity
detection of states. The scalability to large number of qubits, incorporating all the previous
achievements requires an array of linear ion traps. Microfabrication techniques allow
for fabrication and micron level accuracy of the trap electrode dimensions through photolithography
techniques.
The first part of this thesis presents the experiential setup and trapping of Yb+ ions
needed to test large ion trap arrays. This include vacuum systems that can host advanced
symmetric and asymmetric ion traps with up to 90 static voltage control electrodes.
Demonstration of a single trapped Yb+ ion within a two-layer macroscopic ion
trap is presented. with an ion-electrode distance of 310(10) μm. The anomalous heating
rate and spectral noise density of the trap was measured, a main form of decoherence
within ion traps.
The second half of this thesis presents the design and fabrication of multi-layer asymmetric
ion traps. This allows for isolated electrodes that cannot be accessed via surface
pathways, allowing for higher density of electrodes as well as creating novel trap designs
that allow for the potential of quantum simulations to be demonstrated. These include
two-dimensional lattices and ring trap designs in which the isolated electrodes provide
more control in the ion position.
For the microfabrication of these traps I present a novel high-aspect ratio electroplated electrode design that provides shielding of the dielectric layer. This provides a means to mitigate stray electric field due to charge build up on the dielectric surfaces. Electrical testing of the trap structures was performed to test bulk breakdown and surface flashover of the ion trap architectures. Results showed sufficient isolation between electrodes for both radio frequency and static breakdown. Surface flashover voltage measurements over the dielectric layer showed an improvement of more than double over previous results using
a new fabrication technique. This will allow for more powerful ion trap chips needed for the next generation of microfabricated ion trap arrays for scalable quantum technologies
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