Improvement of device characteristics by multiple step implants or introducing a C gettering layer

Ion implantation is used for realization of the collector in vertical bipolar transistors in a BiCMOS process. Secondary defects, remaining after annealing the implant damage, can give rise to an increased leakage current and to collector-emitter shorts. Two methods are proposed to avoid dislocation formation. First, by using multiple step implants, and second, by application of a carbon gettering layer. Experimental results show that these schemes can lower leakage currents, and moreover dramatically increase device yield. However, the carbon profile needs a further optimization with respect to the quality of the collector-substrate junction

Implementing Computer-Based Instructional Programs: A Report from a Rural School

The effective utilization of a new technology requires a proactive approach by administrators

Pre-operative Education for Total Knee Replacement: A Pilot Survey

Purpose: The structure of pre-operative education programs used nationally for patients prior to total knee replacement (TKR) surgery has not been identified previously, thus hospitals across the United States lack a common standard for this pre-operative education to ensure best patient outcomes. The purpose of this pilot survey study was to describe the content, providers, and delivery methods currently utilized to deliver pre-operative education for total knee replacement in the United States. Method: Data were collected using an online survey developed by the authors based on review of literature and three pre-operative programs, and was distributed through the Research Electronic Data Capture (REDCap). The survey consisted of 16 questions, including 12 closed-ended and four open-ended items. Participants were identified through convenience sampling using contacts of the first author and an internet search of hospitals that provide pre-operative education. Seven professional participants total from nursing, physical therapy, and occupational therapy completed the survey. Descriptive statistics were used for data analysis of the 12 quantitative questions to determine frequency and percentages of responses. Responses on the four open-ended survey items, as well as participant responses of “other” for question items, were recorded and collated from individual survey responses. Results: Pre-operative education provider teams for total knee replacements most frequently consisted of nursing, physical therapy, and occupational therapy staff. Most education programs were provided two weeks prior to surgery in a group format, with the majority of programs being delivered in a single session lasting between 1 and 1.5 hours. Verbal and written instruction were the most commonly utilized methods to deliver education. Individual patient programs included a variety of topics, ranging from what to expect while in the hospital, self-care, adaptive equipment, and home safety being some of the most commonly included content. Conclusions: This pilot study provides a framework to describe the structure of pre-operative total knee replacement education nationally, and can be used to guide a future large scale survey to fully describe the content, providers, and delivery methods of pre-operative education for this population across the United States using a representative sample

Pre-Operative Education for Total Knee Replacement: A Pilot Survey

Purpose: The structure of preoperative education programs used nationally for patients prior to total knee replacement (TKR) surgery has not been identified previously, thus hospitals across the United States lack a common standard for this preoperative education to ensure best patient outcomes. The purpose of this pilot survey study was to describe the content, providers, and delivery methods currently utilized to deliver preoperative education for total knee replacement in the United States. Method: Data were collected using an online survey developed by the authors based on review of literature and 3 preoperative programs and was distributed through the Research Electronic Data Capture (REDCap). The survey consisted of 16 questions, including 12 closed-ended and 4 open-ended items. Participants were identified through convenience sampling using contacts of the first author and an Internet search of hospitals that provided preoperative education. Seven professional participants from nursing, physical therapy, and occupational therapy completed the survey. Descriptive statistics were used for data analysis of the 12 quantitative questions to determine frequency and percentages of responses. Responses on the 4 open- ended survey items as well as participant responses of “other” for question items were recorded and collated from individual survey responses. Results: Preoperative education provider teams for total knee replacements most frequently consisted of nursing, physical therapy, and occupational therapy staff. Most education programs were provided 2 weeks prior to surgery in a group format with the majority of programs being delivered in a single session, lasting between 1 and 1.5 hours. Verbal and written instruction were the most commonly utilized methods to deliver education. Individual patient programs included a variety of topics, ranging from the expectations while in the hospital, self-care, adaptive equipment, and home safety, being some of the most commonly included content. Conclusions: With this pilot study, we have provided a framework to describe the structure of preoperative total knee replacement education nationally, which can be used to guide a future large-scale survey to fully describe the content, providers, and delivery methods of preoperative education for this population across the United States, using a representative sample

Pre-Operative Education for Total Knee Replacement: A Pilot Survey

Purpose: The structure of preoperative education programs used nationally for patients prior to total knee replacement (TKR) surgery has not been identified previously, thus hospitals across the United States lack a common standard for this preoperative education to ensure best patient outcomes. The purpose of this pilot survey study was to describe the content, providers, and delivery methods currently utilized to deliver preoperative education for total knee replacement in the United States. Method: Data were collected using an online survey developed by the authors based on review of literature and 3 preoperative programs and was distributed through the Research Electronic Data Capture (REDCap). The survey consisted of 16 questions, including 12 closed-ended and 4 open-ended items. Participants were identified through convenience sampling using contacts of the first author and an Internet search of hospitals that provided preoperative education. Seven professional participants from nursing, physical therapy, and occupational therapy completed the survey. Descriptive statistics were used for data analysis of the 12 quantitative questions to determine frequency and percentages of responses. Responses on the 4 open- ended survey items as well as participant responses of “other” for question items were recorded and collated from individual survey responses. Results: Preoperative education provider teams for total knee replacements most frequently consisted of nursing, physical therapy, and occupational therapy staff. Most education programs were provided 2 weeks prior to surgery in a group format with the majority of programs being delivered in a single session, lasting between 1 and 1.5 hours. Verbal and written instruction were the most commonly utilized methods to deliver education. Individual patient programs included a variety of topics, ranging from the expectations while in the hospital, self-care, adaptive equipment, and home safety, being some of the most commonly included content. Conclusions: With this pilot study, we have provided a framework to describe the structure of preoperative total knee replacement education nationally, which can be used to guide a future large-scale survey to fully describe the content, providers, and delivery methods of preoperative education for this population across the United States, using a representative sample

Erbium in crystal silicon: Optical activation, excitation, and concentration limits

7 pags.; 7 figs.The optical activation, excitation, and concentration limits of erbium in crystal Si are studied. Preamorphized surface layers of Czochralski-grown (Cz) Si(100), containing 1.7×1018 O/cm3, were implanted with 250 keV Er at fluences in the range 8×1011-8×10 14 cm-2. After thermal solid-phase epitaxy of the Er-doped amorphous layers at 600°C, Er is trapped in the crystal at concentrations ranging from 3×1016 to 7×1019 Er/cm 3, as measured by secondary-ion-mass spectrometry. Photoluminescence spectra taken at 77 K show the characteristic Er3+ intra-4f luminescence at 1.54 ¿m. Photoluminescence excitation spectroscopy shows that Er is excited through a photocarrier-mediated process. Rapid thermal annealing at 1000°C for 15 s increases the luminescence intensity, mainly due to an increase in minority-carrier lifetime, which enhances the excitation efficiency. Luminescent Er forms clusters with oxygen: the maximum Er concentration that can be optically activated is determined by the O content, and is (3±1)×1017 Er/cm3 in Cz-Si. The internal quantum efficiency for electrical excitation of Er in Cz-Si is larger than 3×10-6. © 1995 American Institute of Physics.This work is part of the research program of the Foundation for Fundamental Research on Matter (FOM) and was made possible by financial support from the Dutch Organization for the Advancement of Pure Research @IWO), the Netherlands Technology Foundation (STW), and the IC Technology Program (IOP Electra-Optics) of the Ministry of Economic Affairs. R.S. acknowIedges financial support from CSIC, Spain.Peer Reviewe

Direct simulation of ion beam induced stressing and amorphization of silicon

Using molecular dynamics (MD) simulation, we investigate the mechanical response of silicon to high dose ion-irradiation. We employ a realistic and efficient model to directly simulate ion beam induced amorphization. Structural properties of the amorphized sample are compared with experimental data and results of other simulation studies. We find the behavior of the irradiated material is related to the rate at which it can relax. Depending upon the ability to deform, we observe either the generation of a high compressive stress and subsequent expansion of the material, or generation of tensile stress and densification. We note that statistical material properties, such as radial distribution functions are not sufficient to differentiate between different densities of amorphous samples. For any reasonable deformation rate, we observe an expansion of the target upon amorphization in agreement with experimental observations. This is in contrast to simulations of quenching which usually result in denser structures relative to crystalline Si. We conclude that although there is substantial agreement between experimental measurements and most simulation results, the amorphous structures being investigated may have fundamental differences; the difference in density can be attributed to local defects within the amorphous network. Finally we show that annealing simulations of our amorphized samples can lead to a reduction of high energy local defects without a large scale rearrangement of the amorphous network. This supports the proposal that defects in amorphous silicon are analogous to those in crystalline silicon.Comment: 13 pages, 12 figure

West Nile Virus Infections Projected from Blood Donor Screening Data, United States, 2003

Routine donor nucleic acid amplification testing is a valuable surveillance screening tool