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Full-Text Articles in Engineering
Tissue Equivalence Correction In Silicon Microdosimetry For Protons Characteristic Of The Leo Space Environment, Susanna Guatelli, Mark I. Reinhard, B Mascialino, Dale A. Prokopovich, A S. Dzurak, M Zaider, Anatoly B. Rosenfeld
Tissue Equivalence Correction In Silicon Microdosimetry For Protons Characteristic Of The Leo Space Environment, Susanna Guatelli, Mark I. Reinhard, B Mascialino, Dale A. Prokopovich, A S. Dzurak, M Zaider, Anatoly B. Rosenfeld
Susanna Guatelli
The tissue equivalence of solid state silicon detectors in proton radiation fields was determined to improve the radiation protection applications of silicon detectors in aviation and space missions. The study was performed by means of Geant4 simulations. Results are presented showing that a simple geometrical scaling factor (~0.56) of linear dimensions is adequate to convert experimentally obtained microdosimetric energy deposition spectra in silicon to equivalent microdosimetric energy deposition spectra in water.
Dosimetry Verification In Eye Brachytherapy Using Silicon Pixelated Detectors, Michael Weaver, Marco Petasecca, Michael L. Lerch, Dean L. Cutajar, J Jakubek, S Pospsil, Anatoly B. Rosenfeld
Dosimetry Verification In Eye Brachytherapy Using Silicon Pixelated Detectors, Michael Weaver, Marco Petasecca, Michael L. Lerch, Dean L. Cutajar, J Jakubek, S Pospsil, Anatoly B. Rosenfeld
Dean Cutajar
This study presents a high spatial resolution dosimetry system for quality assurance of I-125 eye plaques. The system is based on a silicon pixelated detector and is capable of deriving 3D dose distributions. A simple design was implemented, incorporating a movable eye plaque in a small water phantom above the silicon Medipix2 detector. It is designed for obtaining 2D dose distributions at different depths in water, for subsequent 3D dose mapping. The effect of backscattering in a medium placed behind the Medipix2 to simulate surrounding tissue has been studied in terms of dose distribution. Additionally, two modes of acquisition, event …
From Hep To Medical Radiation Dosimetry - The Silicon Strip Detector Dose Magnifying Glass, J.H.D Wong, Dean Cutajar, Michael Lerch, Marco Petasecca, T Knittel, Martin Carolan, V Perevertaylo, Peter Metcalfe, Anatoly Rosenfeld
From Hep To Medical Radiation Dosimetry - The Silicon Strip Detector Dose Magnifying Glass, J.H.D Wong, Dean Cutajar, Michael Lerch, Marco Petasecca, T Knittel, Martin Carolan, V Perevertaylo, Peter Metcalfe, Anatoly Rosenfeld
Dean Cutajar
High energy physics (HEP) experiments and research gave rise to the development of high spatial resolution tracking vertex detectors and the accompanying data acquisition systems (DAQ) capable of high temporal resolution measurements. The technology translation from HEP to the day to day medical radiation dosimetry is gradual but certain. This paper discusses the design and development of a high spatial resolution (0.2 mm pitch) silicon strip detector referred to as the Dose Magnifying Glass designed and prototyped by the Centre for Medical Radiation Physics (CMRP), University of Wollongong. The DMG has 128 phosphor implanted n+ strips on a p-type silicon …
Silicon/Single-Walled Carbon Nanotube Composite Paper As A Flexible Anode Material For Lithium Ion Batteries, Shulei Chou, Yue Zhao, Jiazhao Wang, Zhixin Chen, Hua-Kun Liu, S. X. Dou
Silicon/Single-Walled Carbon Nanotube Composite Paper As A Flexible Anode Material For Lithium Ion Batteries, Shulei Chou, Yue Zhao, Jiazhao Wang, Zhixin Chen, Hua-Kun Liu, S. X. Dou
Shulei Chou
Flexible silicon/single-walled carbon nanotube (Si/SWCNT) composite paper was prepared using the pulsed laser deposition (PLD) method to deposit Si onto SWCNT paper. In the composite, Si mainly shows nanoworm-like morphology. Increasing deposition time results in an increased amount of Si microspheres. Electrochemical measurements show that the capacity of the composite paper is improved by the presence of Si. The Si/SWCNT composite with only 2.2% Si shows a capacity of 163 mA h g−1 at a current density of 25 mA g−1 up to 50 cycles, which is more than 60% improvement of the capacity of pristine CNT paper. The Si …
Enhanced Reversible Lithium Storage In A Nanosize Silicon/Graphene Composite, Shulei Chou, Jiazhao Wang, Mohammad Choucair, Hua Liu, John Stride, S Dou
Enhanced Reversible Lithium Storage In A Nanosize Silicon/Graphene Composite, Shulei Chou, Jiazhao Wang, Mohammad Choucair, Hua Liu, John Stride, S Dou
Shulei Chou
Si/graphene composite was prepared by simply mixing of commercially available nanosize Si and graphene. Electrochemical tests show that the Si/graphene composite maintains a capacity of 1168 mAh g-1 and an average coulombic efficiency of 93% up to 30 cycles. EIS indicates that the Si/graphene composite electrode has less than 50% of the charge-transfer resistance compared with nanosize Si electrode, evidencing the enhanced ionic conductivity of Si/graphene composite. The enhanced cycling stability is attributed to the fact that the Si/graphene composite can accommodate large volume charge of Si and maintain good electronic contact.
Development And Fabrication Of Cylindrical Silicon-On-Insulator Microdosimeter Arrays, Nai Shyan Lai, Wee Han Lim, Amy L. Ziebell, Mark I. Reinhard, Anatoly B. Rosenfeld, Andrew S. Dzurak
Development And Fabrication Of Cylindrical Silicon-On-Insulator Microdosimeter Arrays, Nai Shyan Lai, Wee Han Lim, Amy L. Ziebell, Mark I. Reinhard, Anatoly B. Rosenfeld, Andrew S. Dzurak
Anatoly Rozenfeld
Recent developments in the fabrication and simulation of prototype silicon-on-insulator (SOI) microdosimeter arrays are presented. A new planar array design has been proposed which has a number of advantages over the previous elongated parallelepiped and cylindrical mesa array designs. This novel planar array design, which incorporates a guard ring, is based upon 2500 planar cylindrically shaped p-i-n detectors and was fabricated via dopant diffusion and ion implantation. The dopant-diffused arrays were successfully fabricated and tested using 2 mum and 10-mum- thick SOI substrates. Technology computer-aided design modeling of the ion-implanted structure is presented which includes the electrostatic potential profile, showing …
A Cylindrical Silicon-On-Insulator Microdosimeter: Charge Collection Characteristics, Amy Ziebell, Wee Han Lim, Mark I. Reinhard, Iwan Cornelius, Dale A. Prokopovich, Rainer Siegele, Andrew S. Dzurak, Anatoly B. Rosenfeld
A Cylindrical Silicon-On-Insulator Microdosimeter: Charge Collection Characteristics, Amy Ziebell, Wee Han Lim, Mark I. Reinhard, Iwan Cornelius, Dale A. Prokopovich, Rainer Siegele, Andrew S. Dzurak, Anatoly B. Rosenfeld
Anatoly Rozenfeld
A novel silicon-on-insulator microdosimeter for estimating the radiobiolgical effectiveness (RBE) of a mixed radiation field is presented. An ion beam induced charge collection study has confirmed the microdosimeter possesses well defined micron sized 3D cylindrical sensitive volumes. An array of these SVs has the capabilitiy of studying the track structure of high energy heavy ions typical of a deep space environment.
Tissue Equivalence Correction In Silicon Microdosimetry For Protons Characteristic Of The Leo Space Environment, Susanna Guatelli, Mark I. Reinhard, B Mascialino, Dale A. Prokopovich, A S. Dzurak, M Zaider, Anatoly B. Rosenfeld
Tissue Equivalence Correction In Silicon Microdosimetry For Protons Characteristic Of The Leo Space Environment, Susanna Guatelli, Mark I. Reinhard, B Mascialino, Dale A. Prokopovich, A S. Dzurak, M Zaider, Anatoly B. Rosenfeld
Anatoly Rozenfeld
The tissue equivalence of solid state silicon detectors in proton radiation fields was determined to improve the radiation protection applications of silicon detectors in aviation and space missions. The study was performed by means of Geant4 simulations. Results are presented showing that a simple geometrical scaling factor (~0.56) of linear dimensions is adequate to convert experimentally obtained microdosimetric energy deposition spectra in silicon to equivalent microdosimetric energy deposition spectra in water.
The Use Of A Silicon Strip Detector Dose Magnifying Glass In Stereotactic Radiotherapy Qa And Dosimetry, J H. D. Wong, T Knittel, S Downes, M Carolan, M L. F. Lerch, M Petasecca, V L. Perevertaylo, P Metcalfe, M Jackson, Anatoly B. Rosenfeld
The Use Of A Silicon Strip Detector Dose Magnifying Glass In Stereotactic Radiotherapy Qa And Dosimetry, J H. D. Wong, T Knittel, S Downes, M Carolan, M L. F. Lerch, M Petasecca, V L. Perevertaylo, P Metcalfe, M Jackson, Anatoly B. Rosenfeld
Anatoly Rozenfeld
Purpose: Stereotactic radiosurgery/therapy (SRS/SRT) is the use of radiation ablation in place of conventional surgical excision to remove or create fibrous tissue in small target volumes. The target of the SRT/SRS treatment is often located in close proximity to critical organs, hence the requirement of high geometric precision including a tight margin on the planning target volume and a sharp dose fall off. One of the major problems with quality assurance (QA) of SRT/SRS is the availability of suitable detectors with the required spatial resolution. The authors present a novel detector that they refer to as the dose magnifying glass …
Fast Scale Prototyping For Folded Millirobots, Aaron Hoover, Ronald Fearing
Fast Scale Prototyping For Folded Millirobots, Aaron Hoover, Ronald Fearing
Aaron M. Hoover
We present a set of tools and a process, making use of inexpensive and environmentally friendly materials, that enable the rapid realization of fully functional large scale prototypes of folded mobile millirobots. By mimicking the smart composite microstructure (SCM) process at a 2–10X scale using posterboard, and commonly available polymer films, we can realize a prototype design in a matter of minutes compared with days for a complicated SCM design at the small scale. The time savings enable a significantly shorter design cycle by allowing forimmediate discovery of design flaws and introduction of design improvements prior to beginning construction at …
A Long-Channel Model For The Asymmetric Double-Gate Mosfet Valid In All Regions Of Operation, Abhishek Kammula, Bradley Minch
A Long-Channel Model For The Asymmetric Double-Gate Mosfet Valid In All Regions Of Operation, Abhishek Kammula, Bradley Minch
Bradley Minch
We present a physically based, continuous analytical model for long-channel double-gate MOSFETs. The model is particularly well suited for implementation in circuit simulators due to the simple expressions for the current andthe continuous nature of the derivatives of the current which improves convergence behavior.
Analyses Of Electroluminescence Spectra Of Silicon Junctions In Avalanche Breakdown Using An Indirect Interband Recombination Model, David Kerns, Sherra Kerns, M Lahbabi, A Ahaitouf, E Abarkan, M Fliyou, A Hoffmann, J Charles, Bharat Bhuva
Analyses Of Electroluminescence Spectra Of Silicon Junctions In Avalanche Breakdown Using An Indirect Interband Recombination Model, David Kerns, Sherra Kerns, M Lahbabi, A Ahaitouf, E Abarkan, M Fliyou, A Hoffmann, J Charles, Bharat Bhuva
Sherra E. Kerns
Light emission from a p-n junction biased in avalanche breakdown has been modeled over the range 1.4–3.4 eV. The model emphasizes indirect interband processes and Si self-absorption. Comparisons between measured and simulated spectra for sample junctions from multiple devices demonstrate that the model is simple, accurate, and consistent with fundamental physical device characteristics.
Analyses Of Electroluminescence Spectra Of Silicon Junctions In Avalanche Breakdown Using An Indirect Interband Recombination Model, David Kerns, Sherra Kerns, M Lahbabi, A Ahaitouf, E Abarkan, M Fliyou, A Hoffmann, J Charles, Bharat Bhuva
Analyses Of Electroluminescence Spectra Of Silicon Junctions In Avalanche Breakdown Using An Indirect Interband Recombination Model, David Kerns, Sherra Kerns, M Lahbabi, A Ahaitouf, E Abarkan, M Fliyou, A Hoffmann, J Charles, Bharat Bhuva
David V. Kerns
Light emission from a p-n junction biased in avalanche breakdown has been modeled over the range 1.4–3.4 eV. The model emphasizes indirect interband processes and Si self-absorption. Comparisons between measured and simulated spectra for sample junctions from multiple devices demonstrate that the model is simple, accurate, and consistent with fundamental physical device characteristics.
Interfacial And Electrokinetic Characterization Of Ipa Solutions Related To Semiconductor Wafer Drying And Cleaning, Jin-Goo Park, Sang-Ho Lee, Ju-Suk Ryu, Yi-Koan Hong, Tae-Gon Kim, Ahmed A. Busnaina
Interfacial And Electrokinetic Characterization Of Ipa Solutions Related To Semiconductor Wafer Drying And Cleaning, Jin-Goo Park, Sang-Ho Lee, Ju-Suk Ryu, Yi-Koan Hong, Tae-Gon Kim, Ahmed A. Busnaina
Jin-Goo Park
In this study, the interfacial and electrokinetic phenomena of mixtures of isopropyl alcohol (IPA) and deionized (DI) water in relation to semiconductor wafer drying is investigated. The dielectric constant of an IPA solution linearly decreased from 78 to 18 with the addition of IPA to DI water. The viscosity of IPA solutions increased as the volume percentage of IPA in DI water increased. The zeta potentials of silica particles and silicon wafers were also measured in IPA solutions. The zeta potential approached neutral values as the volume ratio of IPA in DI water increased. A surface tension decrease from 72 …
Experimental And Numerical Investigation Of Nanoparticle Removal Using Acoustic Streaming And The Effect Of Time, Kaveh Bakhtari, Rasim O. Guldiken, Prashanth Makaram, Ahmed A. Busnaina, Jin-Goo Park
Experimental And Numerical Investigation Of Nanoparticle Removal Using Acoustic Streaming And The Effect Of Time, Kaveh Bakhtari, Rasim O. Guldiken, Prashanth Makaram, Ahmed A. Busnaina, Jin-Goo Park
Jin-Goo Park
Theremoval of nanoparticles is becoming increasingly challenging as the minimumlinewidth continues to decrease in semiconductor manufacturing. In this paper,the removal of nanoparticles from flat substrates using acoustic streamingis investigated. Bare silicon wafers and masks with a 4 nmsilicon cap layer are cleaned. The silicon-cap films are usedin extreme ultraviolet masks to protect Mo–Si reflective multilayers. Theremoval of 63 nm polystyrene latex (PSL) particles from these substratesis conducted using single-wafer megasonic cleaning. The results show higherthan 99% removal of PSL nanoparticles. The results also showthat dilute SC1 provides faster removal of particles, which isalso verified by the analytical analysis. Particle removal …