Multilevel metallization method for fabricating a metal oxide semiconductor device

An improved method is described of constructing a metal oxide semiconductor device having multiple layers of metal deposited by dc magnetron sputtering at low dc voltages and low substrate temperatures. The method provides multilevel interconnections and cross over between individual circuit elements in integrated circuits without significantly reducing the reliability or seriously affecting the yield

High and low threshold P-channel metal oxide semiconductor process and description of microelectronics facility

The fabrication techniques and detail procedures for creating P-channel Metal-Oxide-Semiconductor (P-MOS) integrated circuits at George C. Marshall Space Flight Center (MSFC) are described. Examples of P-MOS integrated circuits fabricated at MSFC together with functional descriptions of each are given. Typical electrical characteristics of high and low threshold P-MOS discrete devices under given conditions are provided. A general description of MSFC design, mask making, packaging, and testing procedures is included. The capabilities described in this report are being utilized in: (1) research and development of new technology, (2) education of individuals in the various disciplines and technologies of the field of microelectronics, and (3) fabrication of many types of specially designed integrated circuits which are not commercially feasible in small quantities for in-house research and development programs

The MSFC complementary metal oxide semiconductor (including multilevel interconnect metallization) process handbook

The fabrication techniques for creation of complementary metal oxide semiconductor integrated circuits at George C. Marshall Space Flight Center are described. Examples of C-MOS integrated circuits manufactured at MSFC are presented with functional descriptions of each. Typical electrical characteristics of both p-channel metal oxide semiconductor and n-channel metal oxide semiconductor discrete devices under given conditions are provided. Procedures design, mask making, packaging, and testing are included

Un método alterno para determinar cationes en solución de muestras pequeñas de suelo

A series of equations based on relations between exchangeable and soil solution ions were evaluated to find an appropriate procedure to determine the activity of cations in soil solution of small soil samples. The effectiveness of the developed equations was maintained even when the sample was submitted to variations in the type of salt added to the soil in the soil water ratio (SWR) used to extract the ions in solution.Se evaluó una serie de ecuaciones basadas en la relación entre iones en solución y en la fase intercambiable del suelo para desarrollar un método que permitiese determinar cationes en solución en muestras de suelo bien pequeñas. Se evaluó uno serie de ecuaciones basadas en la relación entre iones en solución y en la fase intercambiable del suelo para desarrollar un método que permitiese determinar cationes en solución en muestras de suelo bien pequeñas

Characterization of temporal and spatial variation in subwatersheds of the Strawberry River, AR, prior to implementation of agricultural best management practices

Benthic macroinvertebrate (BMI) assessments indicate alterations in physical and/or chemical factors making them valuable tools when attempting to assess agricultural best management practices (BMPs). The purpose of this study was to obtain pre-BMP land cover and macroinvertebrate community data in order to characterize temporal and spatial variation in three catchments: Little Strawberry (LS), Greasy Creek (GC), and Sandy Creek (SC) of the Strawberry River Watershed, located in north central Arkansas, in order to establish baseline conditions. BMIs were collected for the three subwatersheds in 1995, 1999, 2002, 2003 and 2009. Taxa richness, Hilsenhoff Biotic Index (HBI) and Ephemeroptera, Plecoptera and Trichoptera (EPT) score, % dominant taxa, and % Diptera were used as indicators of water quality and habitat changes. All subwatersheds experienced decreased forest land cover indicating land use transition. All resulting BMI measures indicate overall stable habitat and water conditions in the LS subwatershed. Results for GC subwatershed vary with taxa richness, EPT and HBI indicating a stable habitat while increasing % dominant taxa and Diptera indicate a decreasing trend in overall habitat quality. All BMI measures in the SC subwatershed indicate decreasing trend in habitat quality. The most sensitive measure to temporal changes was % Diptera. Trends were not consistent among subwatersheds indicating the importance of continued data collection to establish baseline data and truly monitor changes in aquatic systems over time

Tributary contribution to the Spring River, AR as determined by water quality analyses

Tributaries often play an important role in the chemical properties, productivity and species diversity in a river channel. The objective of this study was to analyze the effect of tributaries on the water quality of the Spring River, AR. The Spring River has an approximate length of 92 km and has been divided into four zones according to the water source(s) that feed that segment of river. In this study approximately 30 km of the upstream river segment were sampled, which included nine tributaries contributing to the main river channel and incorporated the upper three previously defined zones. Samples were collected from the headwaters located at Mammoth Spring, AR, as well as within the tributaries and above and below the confluence of each tributary with the Spring River. Water-quality parameters analyzed included pH, conductivity, alkalinity, total suspended solids, fecal coliforms, nutrients (orthophosphate, nitrate, nitrite), and total dissolved ions. Results of total dissolved ions indicated a slight shift in the defined zones. Seven of the nine tributaries indicated chemical contributions ranging from 3.5 to 66.7% to the main stream. Results from this study demonstrate the extent of tributary contribution to the Spring River systems

Speech-Language Pathology Graduate Student Clinicians’ Self-Perceived Competency in Dysphagia Management

Speech-language pathologists (SLPs) are the preferred healthcare providers for managing the direct clinical care of patients with dysphagia. By assessing self-perceived competency during academic training, SLP graduate student clinicians may increase their understanding of their skills in dysphagia management. We modified the Dysphagia Competency Verification Tool (DCVT) to use a 5-point ordinal scale to explore how SLP graduate student clinicians’ self-perception of competency in dysphagia management changes over time and to determine the impact of clinical practicum experiences. Seventy-two SLP graduate student clinicians rated their self-perceived competency for four DCVT domains. We used Generalized Estimating Equations (GEE) models to analyze the statistical significance of self-perception of competency ratings for each of the DCVT domains across semesters while accounting for clinical practicum experiences. Overall, the SLP graduate student clinicians indicated an increase in DCVT scores from the beginning of their graduate training program to the time of graduation, but did not perceive themselves as Adequate on most items of the DCVT until their last semester. These results suggest that both SLP graduate student clinicians and SLP graduate training programs would benefit from using a standardized metric to assess self-perceived competence in dysphagia management. DCVT self-perceived competency ratings could inform SLP graduate student clinicians about areas of dysphagia management practice and skills that need further development, allowing them to target these specific areas and gain actual competence