bluuebunny/crossref_metadata_2025 huggingface dataset:
Ipsilateral Jugular Access to Treat an Otherwise Inaccessible Puncture-related Arteriovenous Fistula Pseudoaneurysm: A Technical Note
Authors: Rabellino Martin , Rosa-Diez Guillermo , Peralta Oscar , Shinzato Sergio , Crucelegui Maria Soledad , Serra Diego , Garcia-Monaco Ricardo
Published: March 2014

Background

The standard approach for the endovascular treatment of a dysfunctional or occluded hemodialysis access in the upper limbs includes a direct intervention through the access itself or alternatively, when not feasible, through the brachial or radial artery access. Nonetheless, there are certain circumstances in which these approaches are not easily achieved.

Methods

An 89-year-old male with end-stage renal disease developed a pseudoaneurysm after an hemorrhagic complication of a recently transposed native basilic arteriovenous fistula secondary to a needle puncture. Dehiscence of the injured access with spontaneous arterial bleeding evolved as a consequence of the upper limb swelling, rendering therapeutic intervention of the access through a conventional route impossible. A fistulogram through puncture of the common femoral artery was performed to obtain an accurate diagnosis. However, this approach was insufficient to advance the covered stent with the intention of excluding the pseudoaneurysm, as the stent delivery system could not reach the desired site. Given that the covered stent insertion required a 9 Fr introducer, the radial artery approach was ruled out. Therefore, we chose a venous access via the ipsilateral internal jugular vein, which was punctured under ultrasound guidance.

Results

This strategy was useful to advance the stent and exclude the pseudoaneurysm successfully.

Conclusions

This technique should be considered for those individuals in whom conventional routes of approach for repairing dialysis accesses are not feasible or are extremely risky.
Low Rate of Bacteremia with a Subcutaneously Implanted Central Venous access Device
Authors: Nurse Brenda A. , Bonczek Rita , Barton Randall W. , LaRose Daniel T.
Published: March 2014

Purpose

Patients at long-term acute care hospitals (LTACs) are medically complex with multiple comorbidities and high rates of antibiotic and device use. The objective of the study was to analyze the incidence and rate of central line-associated bloodstream infections (CLABSI) and the critical factors for patient care, management, placement and maintenance of the implanted central venous access device at this LTAC.

Methods

A 13-year retrospective chart review was performed comprising 191 medically complex patients with multiple comorbidities who had an implanted central line port. Information analyzed included ( 1 ) number of catheters; ( 2 ) number of patients; ( 3 ) number of catheter line days; ( 4 ) patient demographics; ( 5 ) port location; ( 6 ) admission diagnoses; ( 7 ) type, incidence and rate of catheter-related complications.

Results

The total number of catheter days was over 183,183 with a mean of 959 catheter days per patient. The mean rate of CLABSI was 0.087 per 1,000 days; incidence was less than 8% of patients with catheters.

Conclusions

The study found a markedly lower rate of CLABSI than reported for other LTACs as well as intensive care units, over 14- to 100-fold lower than other LTACs. The authors propose that standardized catheter placement with implementation of rigorous, prospective catheter care plans and a team approach to management were responsible for extremely low complication rates. These results can be extrapolated to different settings across the healthcare continuum.
The Role of Ultrasound as an Adjunct to Arterial Catheterization in Critically Ill Surgical and Intensive Care Unit Patients
Authors: Zochios Vasileios A. , Wilkinson Jonathan , Dasgupta Kausik
Published: March 2014

Objective

To review the evidence behind Ultrasound (US) guided placement of arterial cannulae and its use in the critically ill population.

Data sources

We performed a computer-aided literature search using set search terms and electronic data bases of PubMed and EMBASE from their commencement date through the end of July 2013.

Summary of review

Insertion of intra-arterial catheters is a commonly performed invasive procedure in the peri-operative and intensive care setting that facilitates invasive blood pressure and cardiac output monitoring as well as frequent blood sampling. Arterial catheterization can be particularly challenging in critically ill and high-risk surgical patients with circulatory collapse, low cardiac output state and peripheral edema, all of which can limit the ability to successfully palpate and cannulate the artery. There is a convincing body of evidence suggesting a decrease in complication rate and first-pass success rate in US guided central venous catheter (CVC) insertion compared with the landmark technique. While most intensivists and peri-operative physicians are familiar with US guided CVC placement, fewer use US to guide arterial access.

Conclusions

Most studies have demonstrated a higher success rate when using US guidance for arterial cannulation. Moreover, the technique permits more rapid access and establishment compared with the conventional palpation technique. However, there is evidence opposing the routine use of US to guide arterial cannula insertion. Further studies are required to ascertain the benefits and cost effectiveness of US guided arterial catheterization in peri-operative and critical care.
Managment of renocolic fistula following abdominal trauma from a gunshot: Two cases report
Authors: Abdelaziz Hamdoune , Adourrouj Ilyas , Elabiad Yassine , Janane Abdellatif , Ghadouane Mohammed , Ameur Ahmed , Abbar Mohammed
Published: March 2014

The renocolic fistula is a rare entity. We report 2 cases of renocolic fistula penetrating an abdominal trauma from a gunshot.
Association between R.E.N.A.L nephrometry score and perioperative outcomes following open partial nephrectomy under cold ischemia
Authors: Park Dong Soo , Hwang Jin Ho , Kang Moon Hyung , Oh Jong Jin
Published: March 2014

Introduction: We investigate the clinical significance of the R.E.N.A.L. nephrometry score for renal neoplasm following open partial nephrectomy (PN) under cold ischemia.Methods: A retrospective analysis was conducted using clinical data of 98 consecutive patients with clear cell renal cell carcinoma who underwent open PN by a single surgeon from December 2000 to September 2012. Tumour complexity was stratified into 3 categories: low (4-6), moderate (7-9) and high (10-12) complexity. Perioperative outcomes, such as complications, cold ischemic time, estimated blood loss and renal function, were analyzed according to the complexity by NS. Complications were stratified using the Clavien-Dindo classification system.Results: Tumour complexity according to nephrometry score was assessed as low in 16 (16.3%), moderate in 48 (49.0%) and high in 34 (34.7%). The median cold ischemic time did not differ significantly among the 3 groups (36.0 minutes in low-, 40 minutes in moderate- and 43 minutes in the high-complexity group, p = 0.421). Total complications did not differ significantly (2 (2.0%) in low, 4 (4.1%) in moderate and 4 (4.1%) in high, p = 0.984). Each Grade 3 complication occurred in the moderate (urine leakage) and high groups (lymphocele). Postoperative renal functional outcomes were similar among the groups (p = 0.729). Only mean estimated blood loss was significantly different with nephrometry score (p = 0.049).Conclusions: The nephrometry score, as used in an open PN series under cold ischemia, was not significantly associated with perioperative outcomes (i.e., ischemia time, complications, renal functional preservation).
Injury of the ileum during percutaneous nephrolithotomy in a pediatric patient
Authors: Saad Karim S , Hanno Ahmed , EL-Nahas Ahmed R.
Published: March 2014

Ileum injury during percutaneous nephrolithotomy (PCNL) is an extremely rare complication. We describe the successful management of an inadvertently injured ileum during subcostal PCNL in a 12-year-old boy. Mechanism of injury, presentation and management will be discussed.
Outpatient tubeless percutaneous nephrolithotomy and concomitant cystolitholapaxy
Authors: Lehmann Kyle J , Beiko Darren
Published: March 2014

Percutaneous nephrolithotomy (PCNL) is a widely employed endourologic procedure to remove renal stones. Traditionally, PCNL has been performed on an inpatient basis, with patients routinely hospitalized postoperatively. Given the ongoing rising healthcare costs, a shift toward outpatient surgery is desirable. We report the case of a 21-year-old female who was safely discharged a few hours following uncomplicated tubeless PCNL and concomitant cystolitholapaxy for a stent with encrustation on its distal coil. To the best of our knowledge, this is the first published case of tubeless PCNL with concomitant cystolitholapaxy performed on an entirely outpatient basis.
Rôle de la cystoscopie de fluorescence en lumière bleue induite par Hexvix dans la prise en charge des tumeurs urothéliales vésicales
Authors: Ait Sakel Adil , Mazdar Adil , N'guibou Faustin
Published: March 2014

Objectifs : Évaluer la faisabilité, la fiabilité, le rôle actuel et l’intérêtde la cystoscopie de fluorescence en lumière bleue induite par l’hexaminolévulinate (Hexvix, Photocure ASA) pour la détection des tumeurs urothéliales. Préciser le profil des tumeurs plus particulièrement concernées par cette technique.Patients et méthodes : De janvier 2009 à janvier 2010, une lésion vésicale papillaire typique ou une lésion suspecte a été décelée en cystoscopie chez un total de 30 patients (64 prélèvements). Une résection endoscopique a été réalisée après la détection des lésions vésicales en lumière blanche et en lumière bleue (Hexvix). Une limite de l’étude est l’utilisation répétée d’Hexvix aux fins du suivi de patients porteurs d’un cancer de la vessie n’a pas été étudiée.Résultats : L’âge moyen des patients était de 70 ans (56-84 ans ; 27 hommes et 3 femmes). La cytologie préopératoire s’est révélée positive chez 17 patients, et négative chez 13 patients. Notre étude de 30 patients a permis d’analyser 64 prélèvements. Trente cinq tumeurs papillaires et 10 lésions non papillaires, mais suspectes, ont été repérées en lumière blanche. Cinquante-six prélèvements présentaient une fluorescence positive en lumière bleue, dont 19 lésions étaient seulement décelables sous cette sourcede lumière.Conclusion : Notre étude nous a permis de conclure que la cystoscopiede fluorescence à l’hexaminolé vulinate améliore sensiblement la détection des tumeurs superficielles de la vessie, particulièrement des carcinomes in situ (CIS). De plus, elle permet une résection plus complète qu’en cystoscopie standard à la lumière blanche et diminue le taux de tumeurs résiduelles après résection transurétrale de la vessie (RTUV).
Factors Influencing Adherence to Treatment in COPD Patients and Its Relationship with Disease Exacerbations
Authors: Wiśniewski Dariusz , Porzezińska Maria , Gruchała-Niedoszytko Marta , Niedoszytko Marek , Słomiński Jan , Jassem Ewa
Published: March 2014

Introduction: Chronic obstructive pulmonary disease (COPD) is one of the leading causes of morbidity and mortality in the world. Systematic treatment of COPD decreases symptoms and reduces the frequency of exacerbations and hospitalisations because of the disease. It is estimated that only 50% of patients use prescribed drugs systematically. The aim of this study was to identify the factors which can influence adherence to treatment of the patients who were treated due to exacerbation of COPD. Material and Methods: A questionnaire probe was conducted on 49 patients hospitalised at the Regional Lung and Tuberculosis Hospital in Olsztyn, Poland due to COPD exacerbation. The assessed variables were: quality of life and adherence to treatment 30 days after discharge from hospital in relationship with demographic factors, social status, disease and hospitalisation course, and relief after systematic treatment. Results: Most of the patients assessed their health condition as poor and the disease as limiting their everyday social and occupational activity. 30 days after discharge from hospital the adherence rate to therapy was only 67%. There was an association between systematic treatment and the rate of exacerbations (p = 0.045) and hospitalisations (p = 0.005) but also clinical benefit after long-term treatment (p = 0.023). There were no associations between adherence to treatment and sex, place of residence, education or occupation. Conclusions: Lack of systematic treatment is the main risk factor for COPD exacerbations and hospitalisation rate. A subjective sense of relief after drugs is a factor improving patients’ compliance.
Health-Promoting Activities Performed by Nurses for Patients with COPD
Authors: Dobrowolska Beata , Mazurek Halina , Ślusarska Barbara , Zarzycka Danuta , Charzyńska-Gula Marianna , Cuber Tomasz
Published: March 2014

Wstęp: Przewlekła obturacyjna choroba płuc (POChP) stanowi czwartą przyczynę zgonów na świecie. Wśród działań, które powinna podejmować pielęgniarka w stosunku do chorego na POChP, podkreśla się przede wszystkim znaczenie tych, które można określić jako promujące zdrowie. Celem pracy jest analiza częstości i charakteru podejmowanych przez pielęgniarki działań wchodzących w zakres promocji zdrowia wobec pacjentów z POChP. Materiał i metody: Dokonano analizy ilościowej danych zebranych od 132 pielęgniarek (100%) zatrudnionych w zamkniętej i otwartej opiece zdrowotnej województwa lubelskiego. Zastosowano metodę sondażu diagnostycznego, wykorzystując kwestionariusz ankiety własnego autorstwa. Materiał zgromadzono w 2008 roku. Wyniki: Pielęgniarki pracujące w szpitalach znacznie częściej uczestniczyły w diagnozowaniu POChP (62.30%) aniżeli pielęgniarki podstawowej opieki zdrowotnej (33.40%). Poradnictwo antytytoniowe realizowało 69% respondentów. Badane pielęgniarki rzadko używają profesjonalnych narzędzi do pomiaru i oceny stopnia uzależnienia od nikotyny (6%) oraz do pomiaru poziomu motywacji do walki z nałogiem (4%). Prowadzenie edukacji zdrowotnej wobec chorych na POChP deklarowało 66.67% pielęgniarek z POZ i 76.81% pielęgniarek zatrudnionych w szpitalach. Pielęgniarki nie prowadzą monitoringu udzielanych przez siebie porad oraz nie poddają ocenie ich skuteczności. O udziale w programach wielodyscyplinarnej rehabilitacji oddechowej mówiło tylko 9.53% ankietowanych z POZ oraz 40.58% ankietowanych ze szpitali. Wnioski: Prowadzone przez pielęgniarki działania w stosunku do chorego na POChP mają charakter głównie edukacyjny, niestety są jednak powierzchowne, okazjonalne i nie mają znamion zaplanowanego procesu. Zaleca się planowe, formalne włączenie pielęgniarek w realizację programów promocji zdrowia w grupie chorych na POChP poprzez zaplanowanie środków finansowych na realizowane przez nie zadania, jak również zwrócenie większej uwagi na przygotowanie pielęgniarek do realizacji procesu edukacji zdrowotnej, szczególnie poradnictwa antynikotynowego.
Les compétences informationnelles des étudiants à l’heure du Web 2.0 : proposition d’un modèle pour baliser les formations
Authors: Karsenti Thierry , Dumouchel Gabriel , Komis Vassilis
Published: March 2014

Dans notre société dite du savoir, il est plus important que jamais de former les étudiants aux compétences informationnelles. Par contre, plusieurs universités se limitent trop souvent aux modèles plus classiques de ces compétences, comme celui de l’Association of College & Research Libraries (ACRL 2000), qui ne prennent que trop peu en compte les outils et les possibilités du Web 2.0, avec lesquels sont pourtant si familiers les étudiants. Ce texte présente puis critique les modèles plus traditionnels afin de proposer par la suite un nouveau modèle des compétences informationnelles bonifié et à jour. Nous nous efforcerons de montrer en quoi notre modèle allie à la fois les forces des modèles plus classiques issus de la bibliothéconomie et des sciences de l’information, mais également les avantages et les défis du Web  2.0.
A changing media landscape: Science, the public and the press: The case of climate change
Authors: Priest Susanna
Published: March 2014

Economic restructuring in the media industry has eliminated many professional journalists’ jobs, reductions that may have been hardest on specialized journalists reporting areas like science, technology, economics, or international affairs. This makes audiences even more dependent on new, often social, media for scientific information. The concept of «critical science literacy» is introduced as a way to capture the skills needed to navigate science news in the evolving media landscape. While these same skills were needed to make sense of science in the «old» media world as well, the contemporary shift resulting in attenuation of authoritative journalistic voices is likely to continue, demanding more from audiences. Climate change illustrates these challenges.
The two cultures: Scientists and Journalists, not an outdated relationship
Authors: Peters Hans Peter
Published: March 2014

The relationship between scientists and journalists is much better than its image would suggest. Scientists not only believe that public communication is a duty, but also that media visibility is beneficial. Scientific culture differs from that of journalism, which causes partially discrepant expectations; but in most cases these do not preclude satisfying interactions between journalists and scientists. The traditional relationship between science and journalism is challenged by the rise of new online media. These provide opportunities for scientists and scientific organizations to communicate directly with the public via websites, blogs and social networks. Science journalism may be entering a critical period but it is unlikely that it will fall into decline or be replaced by these new science communications media.
Lenguas minoritarias y divulgación científica. 'Elhuyar': Periodismo y ciencia en Euskera
Authors: Galarraga Ana
Published: March 2014

La revista Elhuyar nació en 1974 con el objetivo de adeucar el euskera al ámbito científico-técnico. Desde entonces, la revista se ha consolidado como una publicación de divulgación de la ciencia que concede especial relevancia a la investigación realizada en el País Vasco, pero cuyo principal objetivo es el de capacitar al lector en la cultura científica y, al mismo tiempo, entrenerlo.
The Brm-HDAC3-Erm repressor complex suppresses dedifferentiation in Drosophila type II neuroblast lineages
Authors: Koe Chwee Tat , Li Song , Rossi Fabrizio , Wong Jack Jing Lin , Wang Yan , Zhang Zhizhuo , Chen Keng , Aw Sherry Shiying , Richardson Helena E , Robson Paul , Sung Wing-Kin , Yu Fengwei , Gonzalez Cayetano , Wang Hongyan
Published: March 2014

The control of self-renewal and differentiation of neural stem and progenitor cells is a crucial issue in stem cell and cancer biology. Drosophila type II neuroblast lineages are prone to developing impaired neuroblast homeostasis if the limited self-renewing potential of intermediate neural progenitors (INPs) is unrestrained. Here, we demonstrate that Drosophila SWI/SNF chromatin remodeling Brahma (Brm) complex functions cooperatively with another chromatin remodeling factor, Histone deacetylase 3 (HDAC3) to suppress the formation of ectopic type II neuroblasts. We show that multiple components of the Brm complex and HDAC3 physically associate with Earmuff (Erm), a type II-specific transcription factor that prevents dedifferentiation of INPs into neuroblasts. Consistently, the predicted Erm-binding motif is present in most of known binding loci of Brm. Furthermore, brm and hdac3 genetically interact with erm to prevent type II neuroblast overgrowth. Thus, the Brm-HDAC3-Erm repressor complex suppresses dedifferentiation of INPs back into type II neuroblasts.
Optical and electrical properties of MoS2 and Fe-doped MoS2
Authors: Wang Song Yu , Ko Tsung Shine , Huang Cheng Ching , Lin Der Yuh , Huang Ying Sheng
Published: March 2014

We prepared undoped and Fe-doped MoS2 layered crystals using a chemical vapor transport method to compare their optical and electrical properties. Optical behaviors of carrier transitions were observed successfully in both undoped and Fe-doped MoS2 samples using reflectance and piezoreflectance. Frequency-dependent photoconductivity (PC) measurements reveal an additional deep Fe doping level for the Fe-doped MoS2 sample. In addition, a longer carrier lifetime was calculated for the Fe-doped MoS2 sample than for the undoped MoS2 sample through PC analysis. Hall measurements were also performed for both samples and indicated that the Fe-doped MoS2 sample exhibited a higher carrier concentration and a lower mobility owing to the effect of Fe dopants. Furthermore, both samples were confirmed to have n-type carriers.
Peak position control of Coulomb blockade oscillations in silicon single-electron transistors with floating gate operating at room temperature
Authors: Tanahashi Yuma , Suzuki Ryota , Saraya Takuya , Hiramoto Toshiro
Published: March 2014

A silicon single-electron transistor (SET) with a floating gate (FG) that covers the entire SET structure is proposed and fabricated to study a nonvolatile and precise peak shift of Coulomb blockade oscillations. Large Coulomb blockade oscillations with a peak-to-valley current ratio as high as 14.1, a parallel peak position control without a change in peak height, and a long retention time of over one month are successfully demonstrated at room temperature. The proposed FG SET is suitable for hybrid SET/CMOS circuits for adding more functionalities into future very large scale integration (VLSI) devices.
Electrochemical impedance spectroscopy in chromatography paper and its application to latex bead detection
Authors: Iwahara Shohei , Miki Masashi , Hori Fumitaka , Uno Shigeyasu
Published: March 2014

The principle of the quantitative immunochromatographic strip test (IST) is proposed. Electrochemical impedance spectroscopy is shown to be capable of detecting latex beads in chromatography paper, where latex beads can serve as a label in IST. Measurements to examine the impedance changes in the absence and presence of latex beads are conducted. In the presence of latex beads, an increase of 12.5% in the bulk solution resistance is observed. This indicates that the latex-bead-labeled antigen–antibody complex can be detected electrochemically by actual IST.
Optimum bandgap profile analysis of Cu(In,Ga)Se2 solar cells with various defect densities by SCAPS
Authors: Murata Masashi , Hironiwa Daisuke , Ashida Naoki , Chantana Jakapan , Aoyagi Kenta , Kataoka Naoya , Minemoto Takashi
Published: March 2014

The bandgap of a Cu(In,Ga)Se2 (CIGS) absorbing layer is varied from 1.0 to 1.7 eV by changing the composition ratio of gallium (Ga), realizing an optimum design for solar cell absorbers. In this study, the effects of a graded bandgap profile on the cell performance of a CIGS solar cell are investigated using a device simulator. Moreover, optimum bandgap profiles with various defect densities are simulated. In the case of low defect densities, when the lowest bandgap, Egmin, is inside the space-charge region (SCR), the double-graded structure is effective for achieving high efficiency. However, when Egmin is outside the SCR, the negative gradient from Egmin to the CIGS surface acts as a barrier that impedes the collection of photogenerated electrons, thereby increasing the recombination rate and decreasing cell efficiency. In the case of high defect densities, to decrease the recombination current and improve the efficiency, a more positive gradient from the back contact to the surface is needed.
(Invited) Applications of Scanning CW Lasers and Electron Beams in Silicon Technology
Authors: Gibbons J. F.
Published: March 2014

Scanning cw laser and electron beams provide an extremely convenient tool for rapidly heating the surface of a semiconductor to a precisely controlled temperature. As a result, they can be used for a variety of semiconductor processing operations, including growth of surface oxides, reduction of Q
ss in deposited oxide films, the annealing of ion implanted layers and the improvement of the electrical properties of both metal silicides and deposited silicon films. Experiments performed to explore these processes will be discussed in this paper.
Short Channel MOS FET's Fabricated by Self-Aligned Ion Implantation and Laser Annealing
Authors: Miyao Masanobu , Koyanagi Mitsumasa , Tamura Hiroshi , Hashimoto Norikazu , Tokuyama Takashi
Published: March 2014

Short channel MOS FET's are successfully fabricated by a combination of selfaligned ion implantation and laser annealing, both of poly-Si gate electrodes. The threshold voltage vs. gate length relation and the overlapping capacitance between gate and drain are improved as a result of the extremely small lateral diffusion of implanted atoms.
Charge Pumping Memory with SOS-MOS Transistors
Authors: Sasaki Nobuo , Nakano Motoo , Iwai Takashi
Published: March 2014

Charge pumping memory cell consists of only one SOS-MOS transistor without any storage capacitor, and is expected to realize a very high density dynamic RAM. The memory array of this cell is studied theoretically and experimentally. The conditions for the selective READ/WRITE operations are described. The method to refresh the cells is also presented.
P-channel Si-gate test devices are fabricated. The selective READ/WRITE operations and the non-destructive readouts are demonstrated. A `1' state is metastable and decays to a `0', but a T state is distinguishable even at 300 µ after the `WRITE `1' operation.
Electron-Hole Pair Generation at the Silicon-Sapphire Interface of SOS Devices
Authors: Lehovec K. , Lin Shi-Tron
Published: March 2014

Transient currents associated with inversion charge build-up in n-type silicon-on-sapphire MOSCs are correlated with steady state reverse currents of a gated p-n diode, and are shown to originate by electron-hole pair generation (EHG) at the sapphire interface under the gate rim. The suppression of EHG elsewhere under the gate is attributed to electron concentration build-up associated with lateral electron diffusion. A spike occurs in the transient at incipient inversion under certain conditions, and is ascribed to a lateral drift field caused by an inversion charge density gradient.
A New Transistor Structure for High Speed Bipolar LSI
Authors: Sakurai Hiromi , Akasaka Yoichi , Murakami Kenji , Kijima Koichi , Nakata Hidefumi
Published: March 2014

A new transistor structure for high speed bipolar LSI, named PEE (Polycrystalline Electrode with Epitaxy) transistor, has been developed especially with respect to base and collector geometry. The basic features of the new structure are ; (1) polycrystalline silicon electrodes for a base and a collector and also polycrystalline silicon resistors, and (2) two-step oxide isolation which enables the bottom side isolation of an extrinsic base to the collector. The new structure can minimize parasitic capacitance, for instance, C

T
C
can be reduced to about half of the conventional oxide isolated structure. This results in a high cutoff frequency of 6.0 GHz. Gate delay time and power-delay product measured with five-stage ECL ring oscillators ranged from 0.74 nsec, 2.8 pJ to 1.3 nsec, 1.8 pJ, and the performance was improved approximately 20% compared with the conventional devices.
(Invited) Recent Progress in Semiconductor Laser Research and Development
Authors: Hayashi Izuo
Published: March 2014

This paper will review recent semiconductor laser research and development, including mode control, materials, degradation and application. It is concerned with understanding of the basic mechanism for laser performance, and its major emphasis is placed on the material and degradation problems.
A new lattice matching technique utilizing the flexibility of the quaternary material has been developed for the (InGa)(AsP)/InP device for one micrometer wavelength range. Vapor phase epitaxial methods using metal organic sources or halide transports have been successful for (AlGa)As and (InGa)(AsP) systems respectively.
Understanding on degradation mechanisms in (AlGa)As device has made progress, but further mechanism studies will be required, including those in other materials for visible and one micrometer ranges.
High-Speed Nonvolatile MNOS/CMOS RAM
Authors: Derbenwick Gary , Dodson William , Sokel Ralph
Published: March 2014

Problems associated with MNOS RAM development are described. The write characteristics of a fast MNOS transistor under constant injecting field are presented and indicate that further speed improvements should result from increasing the injected current for a given write voltage rather than increasing the trap density in the nitride. The dependence of endurance upon several parameters is presented and an electrical screen for endurance is suggested. The major design features of a prototype 1 K×1 metal-gate MNOS/CMOS RAM chip are described.
(Invited) The Buried Channel CCD: an Inherently Reliable Technology
Authors: Amelio G. F. , Chanoski N. W.
Published: March 2014

This paper discusses the reliability analysis of N-BCCD technology which was performed at our laboratories. In order to obtain a complete reliability profile of N-BCCD devices, tests were conducted at the test die level, finished device level and system level. The analysis shows that N-BCCD devices are more immune to oxide related failures compared to RAMS due to the reduced magnitude and negative electric field. Operating life test results taken on our 64 K-bit CCD memory (F464) indicate excellent integrity to oxide related failure modes in the memory array. An introduction and future outlook discussion is given to provide the reader with a perspective on this technology.
CCD Analog-Analog Correlator with Four-FET Bridge Multipliers
Authors: Sage Jay P. , Cappon Arthur M.
Published: March 2014

Design features and experimental results will be presented for a CCD-based monolithic analog-analog correlator using multipliers consisting of four MOSFET's in a bridge arrangement. Each analog input path consists of a dual-channel differential CCD with source-follower-buffered floating-gate non-destructive charge detectors. The principal advantages of this new approach are reduced sensitivity to the following sources of error in previous designs: nonlinearities in the input stage and output taps of the CCD's and in the multiplier MOSFET's; shifts in CCD bias charge level; offsets due to dark current accumulation; fixed-pattern noise due to gradual spatial nonuni formities in dark current generation; and interstage variations in threshold voltages. The balanced multiplier configuration also allows smaller, lower-power source followers to be used to buffer the floating-gate outputs.
Reduced Geometry GaAs CCD for High Speed Signal Processing
Authors: Deyhimy I. , Jr. J. S. Harris, , Eden R. C. , Anderson R. J.
Published: March 2014

A Schottky barrier gate GaAs CCD is described with high transfer efficiency (>0.999/transfer) and ultra-high speed (f
cl.∼500 MHz) operation. Predictions for maximum achievable clock frequency are made, and possible signal processing applications are discussed.
2 GHz, High Power Silicon SIT's
Authors: Shino Toshio , Kamo Hisao , Aoki Kiyoshi , Okano Susumu
Published: March 2014

Silicon SIT's (Static Induction Transistors) have been developed, which deliver a power output of 9.1 W (3.6 dB gain, 30% drain efficiency) at 2.1 GHz and 12 W (2.3 dB gain, 28% drain efficiency) at 2.0 GHz. A fine patterned structure of the SIT's was fabricated with the “washed gate” process and chemical dry etching technique. The structure to improve source-to-gate breakdown voltage was also adopted. The channel resistivity and the thickness of epitaxial layer were optimized for operations at around 2 GHz. An internal matching technique was applied to reduce the effects of matching circuit loss.
Stationary and Transient Thermal Simulation and Its Use in Power IC Design
Authors: Antognetti P. , Bisio G. R. , Curatelli F. , Palara S.
Published: March 2014

Thermal effects may represent a limiting factor in the development of integrated circuits. As the power dissipated by integrated circuits becomes more relevant, the need increases for more accurate modelling of the stationary and transient thermal behaviour of the die-package structure. In this paper, an analytical solution of the three-dimen-sional transient thermal diffusion problem is presented, together with a simple computer program for the calculation of the solution. The program, implemented on a minicomputer, is proven to be fast and accurate. The simulation technique is then applied to the design of a new short-circuit protection of a 6A current booster.
(Invited) Recent Progress and Potential of SIT
Authors: Nishizawa Jun-ichi
Published: March 2014

Static induction transistor (SIT) has been demonstrated experimentally to achieve high power, high frequency and high current, high speed and high efficiency devices for analogue and switching applications. Low energy, high speed and high packing density integrated circuits are also possible.
Fundamental superiorities of SIT compared with conventional FET and bipolar transistor are discussed in this manuscript to describe performances of junction gate SIT and MIS SIT. Discussions are concentrated on the role of the negative feedback action due to the series resistance, the minority carrier storage effect and the feedback mechanism due to the virtual base resistance.
MSI High Speed Low Power GaAs Integrated Circuits
Authors: Long S. I. , Welch B. M. , Eden R. C. , Lee F. S. , Zucca R.
Published: March 2014

A new planar, high density (10-3 mm2/gate) GaAs IC technology has been used for fabricating MSI digital circuits containing up to 75 gates per chip. These circuits consist of Schottky diode FET logic NOR gates, which have provided propagation delays in the 80–200 ps range with dynamic switching energies as low as 27 fJ/gate on ring oscillator structures. Power dissipation levels are compatible with future LSI/VLSI extensions. Operation of D-flip flops as binary ripple dividers (\div2 to \div8) was achieved at 1.9 GHz clock rates, and an 8: 1 full data multiplexer and 1: 8 data demultiplexer were demonstrated at 1.1 GHz clock rates. This corresponds to equivalent propagation delays in the 100 to 175 ps range for these MSI circuits. Finally, a 3×3 parallel multiplier containing 75 gates functioned with a propagation delay of 172 ps/gate and with average gate power dissipations of as low as 420 µW/gate.
High Speed Enhancement-Mode GaAs MESFET Integrated Circuits
Authors: Mizutani Takashi , Kato Naoki , Ishida Satoru , Asai Kazuyoshi , Sakakibara Yutaka , Komatsu Kazuhiko , Ohmori Masamichi
Published: March 2014

Enhancement-mode GaAs MESFET logics fabricated by electron beam lithography have shown high speed and low power dissipation characteristics. A minimum propagation delay time of 77 ps at a power dissipation of 977 µW was obtainsd for a 0.8 µm gate length ring oscillator. A minimum power-delay product was 1.6 fJ at a propagation delay time of 200 ps.
Low temperature operation was also performed and higher switching speed was obtained. The minimum propagation delay time was 44 ps and the associated power dissipation was 2.9 mW at liquid nitrogen temperature.
VLSI GaAs Tunnel Diode-FET Logic and Memory Cell
Authors: Lehovec Kurt
Published: March 2014

A micro-tunnel diode load for a normally off, enhancement mode field effect transistor operated at a supply voltage about equal to the valley-current voltage of the tunnel diode provides the basic building block for a compact dc coupled high speed VLSI logic1) for which the name TDFL is suggested. The pertinent unique properties of the micro-tunnel diode are: a low current when the supply voltage extends across the diode, hence low power dissipation; a large pull-up current during the major portion of the rise transient of the inverter, hence short rise time; and an extremely small area negligible vs the switching transistor area. The speed advantage of the tunnel diode load over conventional loads becomes more pronounced at higher fan-out ratios eliminating the need for buffers in many cases. The negative resistance characteristic of the tunnel diode also enables the design of a compact static memory element.
Flip-Chip Mounted GaAs Power FET with Improved Performances in X to Ku Band
Authors: Mitsui Yasuo , Kobiki Michihiro , Wataze Manabu , Otsubo Mutsuyuki , Ishii Takashi , Mitsui Shigeru
Published: March 2014

A GaAs power field effect transistor with a new structure has been developed, in which source inductances and thermal resistance are remarkably reduced. In the structure, the chip with metal posts plated on the source, drain and gate pads is directly connected to the corresponding bonding area of a package by thermocompression bonding with no wire. Best results obtained are 2.5 W at 15 GHz, 4.1 W at 12 GHz and 6.0 W at 10 GHz. A power added efficiency as high as 27% is obtained in a 2400 µm device at 12 GHz.
Investigation on the Drift of GaAs MESFET's by High Frequency Parameters
Authors: Ohata Keiichi , Itoh Hitoshi , Hasegawa Fumio
Published: March 2014

The long term drift of GaAs MESFET's performance was investigated by measuring a change of the equivalent circuit parameters at high frequencies. It was found that the drain conductance and the drain-gate feedback capacitance of the MESFET's decrease remarkably corresponding to the drift of the drain current, and they are not recovered even after the drain current is reset to the original value. These changes of the equivalent circuit parameters are different from the changes observed when a bias is applied on the substrate, and they can be eliminated by an appropriate surface passivation.
The change of the equivalent circuit parameters can be explained as the result of the gradual expansion of the surface depletion region from the gate to the drain area.
Tin Diffusion from Doped Oxides for Fabricating GaAs Microwave Devices
Authors: Arnold Norbert , Daembkes Heinrich , Heime Klaus
Published: March 2014

Doped oxides have been used as solid diffusion sources and surface protection layers for diffusion into Cr-doped GaAs. Surface passivation during diffusion at 900°C for 45 min is good and nearly undamaged surfaces have been obtained. The carrier concentration profiles of such diffusions, determined by C-V-measurements, show a steep decrease at about 0.16 µm depth from the surface and can be explained by a concentration dependent diffusion coefficient. 1.3 µm gate length MESFETs produced from diffused layers show excellent I-V characteristics with transconductances up to 120 mmho per mm gate width.
pInxGa1-xSb–nGa1-yAlySb Heterojunction Photodiodes
Authors: Mizuki Toshio , Sugimoto Yoshimasa , Tanaka Akira , Sukegawa Tokuzo
Published: March 2014

Highly efficient, lattice-matched heterojunction photodiodes were fabricated by liquid-phase-epitaxial growth of a pIn0.07Ga0.93Sb layer, followed by an nGa0.3Al0.7Sb layer on the p-type (111) GaSb substrate. The spectral photocurrent response of the diodes was nearly flat in the wavelength range of 1.0–1.8 µm. The external guantum efficiency of photodiodes was 32% at zero voltage bias in the vicinity of 1.5 µm where a minimum loss of optical fibre was reported.
Partially Homogeneous Broadening and Saturation in Semiconductor Lasers
Authors: Gamo Hideya
Published: March 2014

By introducing homogeneous and inhomogeneous linewidths and saturation irradiance, the gain and phase constants of semiconductor laser amplifiers are formulated in terms of the Voigt function and its Hilbert transform, in accordance with those for gas laser amplifiers with partially homogeneous broadening. The suppression of nonoscillating modes by a predominant oscillating mode well above the oscillation threshxsold is shown to be caused by the diffusion of excess electrons/holes. By defining the coupling coefficient between two adjacent modes, we discuss possible physical origin of the strong coupling in CSP semiconductor lasers.
1.5–1.6 µm Wavelength (100) GalnAsP/InP DH Lasers
Authors: Arai Shigehisa , Itaya Yoshio , Suematsu Yasuharu , Kishino Katsumi
Published: March 2014

Long wavelength (100) GalnAsP/InP DH lasers in the range of 1.45–1.65 µm were obtained by two-phase solution technique using an “anti-meltback” layer which consists of a quaternary crystal and was attached on the active layer. Low normalized threshold current density J
th/d of 5–6 KA/cm2/µm was obtained. The threshold current density less than 2 KA/cm2 was obtained. The temperature dependence of lasing wavelength was about 5 Å/deg. at λ=1.55 µm. The spontaneous spectral width of 1.55 µm laser was 1400 Å at room temperature. Lasing thresholds of these laser diodes increased rapidly with the temperature at around 250 K.
(Invited) Ga1-xAlxAs–GaAs Heterostructure Lasers Grown by Metalorganic Chemical Vapor Deposition
Authors: Dupuis Russell D.
Published: March 2014

High-performance room-temperature Ga1-x
Al
x
As–GaAs double-heterostructure injection lasers have been grown by the use of metalorganic and hydride sources. This metalorganic chemical vapor deposition process is well-suited for the large-scale production of these devices. This paper will describe the preparation and properties of injection lasers grown by this process.
Catastrophic Optical Damage Generation Mechanism in (AlGa)As DH Lasers
Authors: Kamejima Taibun , Yonezu Hiroo
Published: March 2014

Under high optical power operation, (AlGa)As DH lasers suffer from catastrophic optical damage (COD). When the COD occurs <110> dark line defects are observed in the bulk crystal, as well as in mirror surface damage. The COD generation mechanism is clarified by TEM observation of the defects associated with the COD and by investigation on transient behaviors of lasing light excited by one-shot-pulse. It is confirmed that such defects are generated by local overheating up to the melting point of GaAs due to
the thermal positive feed back and following transfer of molten zone.
1: 4 Demagnifying Electron Projection System
Authors: Asai Takayuki , Ito Shin-ichi , Eto Toshio , Migitaka Masatoshi
Published: March 2014

Reported here are the features of a 1: 4 demagnifying electron projection system, its imaging method and alignment procedures.
Use of a new projection system with a small, parallel illumination beam at the mask plane plus a raster scan to cover the entire mask has made it possible to obtain high alignment accuracy as well as a large image field with a relatively small electron optical column.
A linewidth of 0.5 µm and the distortion of less than 1% over an image field of 3 mm square were obtained experimentally. An alignment accuracy achieved is ±0.2 µm.
A New Heat Treatment Technique for No Thermal Conversion of Semi-Insulating GaAs Wafers
Authors: Tanaka Toshio , Takamiya Saburo , Susaki Makoto Ishii
Published: March 2014

Cr-doped semi-insulating GaAs wafers usually suffer thermal conversion by heat treatment at high temperature prior to epitaxial growth. In this paper, the influence of a small amount of AsCl3 gas, added into H2 atmosphere, on the thermal conversion of the semi-insulating GaAs wafers have been investigated. Resistivity, surface morphology, and photoluminescence spectra of the wafers before and after a heat treatment at 800°C for 1.5 hours, were examined. It is found that no thermal conversion occurs by controlling an AsCl3 concentration in the hydrogen-ambient gas flow at 2.8×10-4 mol%.
Selective Plasma Oxidation of GaAs –A Study of the Interface Properties
Authors: Chang R. P. H.
Published: March 2014

Studies by electron and photon spectroscopy show that plasma grown GaAs oxide possesses an excess amount elemental As at the oxide–GaAs interface. This amount has been found to be inversely proportional to the growth rate. The excess elemental As is deleterious to the electrical properties of MOS devices. A selective plasma oxidation process using fluorinated oxygen gas shows that the excess As at the interface can be greatly reduced. The resultant electrical properties are also improved.
Low Temperature Alloyed Contact Formation in Various Metal-Semiconductor Couples
Authors: Iwami Motohiro , Kim Su Chol , Kammura Wako , Hiraki Akio
Published: March 2014

Metal (Au, Cu, or Pd)/semiconductor (InSb, InP, or GaP) contact systems were studied by Auger electron spectroscopy with the aid of Ar+ ion sputtering. For all systems, even at room temperature, considerable fractions of atoms constituting semiconductors were found to accumulate on metal surfaces, indicating ready interfacial interaction between these materials. From the depth profiling of the specimens, the existence of alloyed interface regions or low temperature alloyed contact formation was ascertained. From these results in addition to our previous data, the alloyed contact formation at metal-semiconductor interface is discussed in connection with the mechanism of Fermi-level pinning in the problem of metal-semiconductor potential barriers.
Ion Implantation Study of HgCdTe
Authors: Bubulac L. O. , Tennant W. E. , Shin S. H. , Wang C. C. , Lanir M. , Gertner E. R. , Marshall E. D.
Published: March 2014

Light atom species, such as Li, Mg, B, Be, Cl, F and Al implanted in bulk and epitaxial HgCdTe of compositions from 3 to 12 µm cut-off yielded n/p junctions. The nature of these junctions has not previously been understood. Implantation of light atoms has been observed to induce n-type electrically active defects which propagate deep into the material during the implantation process. The experiments, performed on an epitaxial wafer of ∼5 µm cut-off wavelength, showed an electron profile of the implanted layer 3 to 4 times deeper than the mean projected range determined by SIMS measurements. The results are in good agreement with the graded junction profile determined from C-V measurement, and have junction depths of 2–3 µm determined from EBIC measurements. It has been concluded that the junction formation mechanism in HgCdTe is determined primarily by radiation induced mobile defects.
Quantitative Analysis of Semiconductor Materials with Secondary Ion Mass Spectrometer
Authors: Oshima Masaharu , Kawashima Izumi , Yoshii Shizuka
Published: March 2014

A simplified quantitative procedure for SIMS, based on the LTE (Local Thermal Equilibrium) model, was proposed and applied to Na concentration determination in Si and SiO2. The procedure validity was checked using In0.1Ga0.9As and PSG (phospho-silicate glass) films as standard samples. Na concentration determination was carried out using a Si wafer, whose C
Na was measured by activation analysis. In the case of SiO2, borosilicate glasses were analyzed taking into account Na ionization yield. Then, Na distribution in SiO2 films was measured by SIMS and was compared with the total amount of Na in SiO2 films obtained by electrical measurement and Atomic Absorption Spectrophotometry (AAS).
Electron Beam Mask Fabrication for MOSLSI's with 1.5 µm Design Rule
Authors: Okazaki Shinji , Mochiji Kozo , Takeda Eiji , Maruyama Yoji
Published: March 2014

A new mask set for n-MOSFET test devices and circuits is made to investigate the feasibility of electron beam mask fabrication with very small linewidths. The mask set is basically designed with a 1.5 µm design rule, but contained finer lines to clarify problem areas. A negative electron resist PGMA and a positive electron resist P(MMA-AN) are used. Linewidth control is better than ±0.1 µm with PGMA and ±0.2 µm with P(MMA-AN). Pattern placement accuracy is ±0.15 µm and overlay accuracy is ±0.25 µm. The characteristics of MOSFET's and RAM's fabricated using the 1.5 µm design rule masks, are measured.