Characterization of FBK small-pitch 3D diodes after neutron irradiation up to 3.5x10**16 neq cm**-2

We report on the characterization by a position resolved laser system of small-pitch 3D diodes irradiated with neutrons up to an extremely high fluence of 3.5x10**16 neq cm**-2. We show that very high values of signal efficiency are obtained, in good agreement with the geometrical expectation based on the small values of the inter-electrode spacings, and also boosted by charge multiplication effects at high voltage. These results confirm the very high radiation tolerance of small-pitch 3D sensors well beyond the maximum fluences expected at the High Luminosity LHC.Comment: 10 pages, 7 figures, submitted to Proceedings of IWORID 2018 on JINS

Progress in 3D Silicon Radiation Detectors

In the past few years, there has been an increasing interest toward 3D silicon radiation detectors. Owing to their unique architecture, 3D detectors provide a remarkable radiation hardness at relatively low bias voltage (hence low power dissipation), that makes them the most appealing solution for use in the innermost layers of tracking detectors in High Energy Physics (HEP) experiments. Besides this primary application, the use of 3D sensor technology has been extended also to other fields, like thermal neutron detection and microdosimetry for proton and ion therapy. In this paper, we will review the state of the art and on going efforts in 3D detectors, covering the main design and technological issues, as well as selected results from the experimental characterization and TCAD simulation.publishedVersio

Development of New 3D Pixel Sensors for Phase 2 Upgrades at LHC

We report on the development of new 3D pixel sensors for the Phase 2 Upgrades at the High-Luminosity LHC (HL-LHC). To cope with the requirements of increased pixel granularity (e.g., 50x50 or 25x100 um2 pixel size) and extreme radiation hardness (up to a fluence of 2e16 neq cm-2), thinner 3D sensors (~100 um) with electrodes having narrower size (~ 5 um) and reduced spacing (~ 30 um) are considered. The paper covers TCAD simulations, as well as technological and design aspects relevant to the first batch of these 3D sensors, that is currently being fabricated at FBK on 6-inch wafers.Comment: 4 pages, 8 figures, 2015 IEEE Nuclear Science Symposium and Medical Imaging Conferenc

Mapeamento da soja por meio de técnicas de sensoriamento remoto nos municípios de Lages e Capão Alto - estado de Santa Catarina

TCC (graduação) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Agronomia.O objetivo deste trabalho foi mapear a área plantada de soja nos municípios de Lages e Capão Alto através de técnicas de sensoriamento remoto nas safras 2012/2013 e 2020/2021. Foram utilizadas imagens dos satélites Landsat-7, Landsat-8 e Sentinel-2 e a identificação das áreas foi feita através de interpretação visual das imagens multitemporais submetidas a uma composição RGB que permitiu que a soja se destacasse em meio aos demais alvos da cena. Os resultados obtidos neste trabalho foram comparados com dados de monitoramento de safra realizado pela Epagri/Cepa, apresentando valores acima dos dados oficiais. Através do mapeamento, foi constatado um aumento de área de 13 mil ha entre as safras 2012/2013 e 2020/2021. O cruzamento das áreas de expansão de soja com classes de uso do solo mostraram que a conversão tem ocorrido, principalmente, sobre campos nativos. Além disso, o confronto com dados de altitude e declividade indicam que a expansão tem migrado para áreas mais altas e se mantido na classe de relevo suave-ondulada. O uso de técnicas de sensoriamento remoto permitiu o mapeamento das áreas de soja, através de uma metodologia possível de ser aplicada também em outros locais de estudo.The main of this study was to map the soybean crop area in the municipalities of Lages and Capão Alto through remote sensing techniques in the 2012/2013 and 2020/2021 harvests. Landsat-7, Landsat-8 and Sentinel-2 satellite images were used and the identification of the areas was made by visual interpretation of the multitemporal images submitted to a RGB composition that allowed the soybean to stand out among the other targets in the scene. The results obtained in this study were compared with crop monitoring data carried out by Epagri/Cepa, presenting values above the official data. Through the mapping, an increase in area of 13 thousand ha was found between the 2012/2013 and 2020/2021 harvests. The crossing of soybean expansion areas with land use classes showed that conversion has occurred mainly over native fields. In addition, the comparison with altitude and slope data indicates that the expansion has migrated to higher areas and remained in the smooth-wavy class. The use of remote sensing techniques allowed the mapping of soybean crop areas, through a methodology that could also be applied in other study areas. Keywords: remote sensing, soybean, geotechnologies, agricultural monitorin

Mapeamento da soja por meio de técnicas de sensoriamento remoto nos municípios de Lages e Capão Alto - Estado de Santa Catarina

TCC (graduação) - Universidade Federal de Santa Catarina. Centro de Ciências Agrárias. Curso de Agronomia.O objetivo deste trabalho foi mapear a área plantada de soja nos municípios de Lages e Capão Alto através de técnicas de sensoriamento remoto nas safras 2012/2013 e 2020/2021. Foram utilizadas imagens dos satélites Landsat-7, Landsat-8 e Sentinel-2 e a identificação das áreas foi feita através de interpretação visual das imagens multitemporais submetidas a uma composição RGB que permitiu que a soja se destacasse em meio aos demais alvos da cena. Os resultados obtidos neste trabalho foram comparados com dados de monitoramento de safra realizado pela Epagri/Cepa, apresentando valores acima dos dados oficiais. Através do mapeamento, foi constatado um aumento de área de 13 mil ha entre as safras 2012/2013 e 2020/2021. O cruzamento das áreas de expansão de soja com classes de uso do solo mostraram que a conversão tem ocorrido, principalmente, sobre campos nativos. Além disso, o confronto com dados de altitude e declividade indicam que a expansão tem migrado para áreas mais altas e se mantido na classe de relevo suave-ondulada. O uso de técnicas de sensoriamento remoto permitiu o mapeamento das áreas de soja, através de uma metodologia possível de ser aplicada também em outros locais de estudo.The main of this study was to map the soybean crop area in the municipalities of Lages and Capão Alto through remote sensing techniques in the 2012/2013 and 2020/2021 harvests. Landsat-7, Landsat-8 and Sentinel-2 satellite images were used and the identification of the areas was made by visual interpretation of the multitemporal images submitted to a RGB composition that allowed the soybean to stand out among the other targets in the scene. The results obtained in this study were compared with crop monitoring data carried out by Epagri/Cepa, presenting values above the official data. Through the mapping, an increase in area of 13 thousand ha was found between the 2012/2013 and 2020/2021 harvests. The crossing of soybean expansion areas with land use classes showed that conversion has occurred mainly over native fields. In addition, the comparison with altitude and slope data indicates that the expansion has migrated to higher areas and remained in the smooth-wavy class. The use of remote sensing techniques allowed the mapping of soybean crop areas, through a methodology that could also be applied in other study areas

Agricultura familiar agroecológica e os desafios da extensão rural no Oeste Catarinense

TCC (graduação) - Universidade Federal de Santa Catarina. Centro de Ciências Agrárias. Curso de Agronomia.A agricultura familiar na mesorregião Oeste Catarinense está profundamente relacionada com a formação social e econômica daquele território. No contexto atual, com a intensa urbanização e modernização de técnicas agrícolas, grande é o número de agricultores sofrendo com a exclusão social. A agroecologia se apresenta como uma oportunidade valiosa de geração de renda, bem-estar e sustentabilidade, possível de ser praticada em pequenas propriedades e coerente com as demandas dos consumidores. No entanto, para que os agricultores sejam bem sucedidos nessa empreitada, se faz necessário que suas demandas em relação à extensão rural agroecológica sejam atendidas. Estudos apontam para uma insatisfação dos agricultores familiares em relação a essa atuação. O objetivo desse estudo foi o de identificar os fatores que estão restringindo esse acesso à extensão rural por parte dos agricultores familiares orientados por princípios agroecológicos da região oeste do estado. Para elucidar essa questão além de uma revisão bibliográfica sobre as temáticas envolvidas, foram realizadas entrevistas semi-estruturadas com agricultores familiares orientados por princípios agroecológicos e também questionários com extensionistas rurais que atuam na área. A análise de conteúdo das entrevistas foi fundamentada na seleção de categorias, características e indicadores significativos dos conceitos vinculados com o objeto de estudo. Concluiu-se que o modelo de extensão rural demandado pelas famílias de agricultores é composto de dez principais demandas que, em geral, não estão sendo atendidas devido ao número inadequado de profissionais disponíveis, a falta de articulação entre as esferas federais, estaduais e locais envolvidas com extensão a rural, e a falta de apoio das lideranças dessas mesmas esferas ao projeto agroecológico

TCAD Analysis of Leakage Current and Breakdown Voltage in Small Pitch 3D Pixel Sensors

Small-pitch 3D pixel sensors have been developed to equip the innermost layers of the ATLAS and CMS tracker upgrades at the High Luminosity LHC. They feature 50 × 50 and 25 × 100 μm2 geometries and are fabricated on p-type Si-Si Direct Wafer Bonded substrates of 150 μm active thickness with a single-sided process. Due to the short inter-electrode distance, charge trapping effects are strongly mitigated, making these sensors extremely radiation hard. Results from beam test measurements of 3D pixel modules irradiated at large fluences (1016neq/cm2) indeed demonstrated high efficiency at maximum bias voltages of the order of 150 V. However, the downscaled sensor structure also lends itself to high electric fields as the bias voltage is increased, meaning that premature electrical breakdown due to impact ionization is a concern. In this study, TCAD simulations incorporating advanced surface and bulk damage models are used to investigate the leakage current and breakdown behavior of these sensors. Simulations are compared with measured characteristics of 3D diodes irradiated with neutrons at fluences up to 1.5 × 1016neq/cm2. The dependence of the breakdown voltage on geometrical parameters (e.g., the n+ column radius and the gap between the n+ column tip and the highly doped p++ handle wafer) is also discussed for optimization purposes

First Production of New Thin 3D Sensors for HL-LHC at FBK

Owing to their intrinsic (geometry dependent) radiation hardness, 3D pixel sensors are promising candidates for the innermost tracking layers of the forthcoming experiment upgrades at the Phase 2 High-Luminosity LHC (HL-LHC). To this purpose, extreme radiation hardness up to the expected maximum fluence of 2e16 neq.cm-2 must come along with several technological improvements in a new generation of 3D pixels, i.e., increased pixel granularity (50x50 or 25x100 um2 cell size), thinner active region (~100 um), narrower columnar electrodes (~5 um diameter) with reduced inter-electrode spacing (~30 um), and very slim edges (~100 um). The fabrication of the first batch of these new 3D sensors was recently completed at FBK on Si-Si direct wafer bonded 6-inch substrates. Initial electrical test results, performed at wafer level on sensors and test structures, highlighted very promising performance, in good agreement with TCAD simulations: low leakage current (<1 pA/column), intrinsic breakdown voltage of more than 150 V, capacitance of about 50 fF/column, thus assessing the validity of the design approach. A large variety of pixel sensors compatible with both existing (e.g., ATLAS FEI4 and CMS PSI46) and future (e.g., RD53) read-out chips were fabricated, that were also electrically tested on wafer using a temporary metal layer patterned as strips shorting rows of pixels together. This allowed a statistically significant distribution of the relevant electrical quantities to be obtained, thus gaining insight into the impact of process-induced defects. A few 3D strip test structures were irradiated with X-rays, showing inter-strip resistance of at least several GOhm even after 50 Mrad(Si) dose, thus proving the p-spray robustness. We present the most important design and technological aspects, and results obtained from the initial investigations.Comment: 8 pages, 7 figures, 2016 IWORI