Une équipe de scientifiques et techniciens travaillant dans le domaine du développement de semiconducteurs optiques ont fondé en 2003 la sglux GmbH. En étroite coopération avec des instituts de recherche et en partenariat avec le client, leur travail est inspiré et motivé par le souhait de transférer les innovations scientifiques au marché des composants de mesures UV. Veuillez trouver ci-dessous une liste des projets actuels et finalisés.
Research project within the 20zwanzig initiative « Advanced UV for life »
Période: 2016 – 2020
Numéro du projet: BMBF 03ZZ0123
Abstrait
Within the UV-Aging project experimental setups and scientific method are developed to allow a reliable estimation of the degradtion behavior of LED and photodiodes as well as components used in these products (glass, diffusors, reflectors, glues, etc.). In the beginning a UV-Aging chamber will be constructed which allows the control of UV light (UV-A, B & C), temperature (up to 170°C) and humidity (95% r.h.).
Période: 2016 – 2018
Numéro du projet: BMBF 03ZZ0119A
Abstrait
This project aims at the development of optics, electronics and software for miniaturized SiC UV spectrometers and camera modules. sglux as the first company worldwide is working on a new product family of Silicon Carbide (SiC) based UV spectrometers (up to 1024 pixel resolution). The advantage of such UV spectrometers results from the extreme radiation hardness and very high visible blindness of SiC compared with Silicon (Si) based UV spectrometers leading to negligible degradation and zero stray light effects caused by visible light. This new spectrometer technology allows precise UV spectrometry also at presence of strong visible light such as UV measurements in the bright sun (e.g. UV Index spectroscopy) or under room light. Another advantage of the SiC UV spectrometer results from the high radiation hardness and low dark current of this material. These features lead to a broader dynamic range of the spectrometer compared with conventional Si based spectrometers. Spectrometers with a 128 pixel resolution are available for evaluation purpose.
Période: 2014 – 2018
Abstrait
Measurement and calibration facilities and calibration methods for high UV irradiation will be established within this project. These methods will accord to the calibration procedures of the Physikalisch-Technische Bundesanstalt (PTB) and will allow sglux to offer novel industry-based calibration services. Hereby the project is focussing on the UV curing industry. Based on results of a corporate BMWi ZIM project, reference radiometers and standard sources with high UV irradiation will be optimized for this application field.
Période: 2017 – 2018
Abstrait
The UV-Index according to ISO 17166 is a measure of the risk of sunburn (erythema solare) at a given solar irradiance. Governmental meteorological institutes measure the UV-Index with spectroradiometers. Due to high investment and maintenance costs of these spectroradiometers, the use of small, rugged and low maintenance UV-Index-Radiometers should be a matter of evaluation, in particular when meteorological networks are planned to be extended.
To evaluate the performance these UV-Index-Radiometers, basically the measurement uncertainty needs to be investigated and compared with the measurement uncertainty obtained by spectroradiometers. Egli et al.¹ report the typical UV-Index-spectrometer measurement uncertainty with ± 5 %. To investigate the measurement uncertainty of UV- Index-Radiometers, a bundle of 2073 different sun spectra with a range from UVI 0.5 until UVI 13.5 was used. They were traceably obtained at different places at the earth where the solar situation was influenced by latitude, altitude, season and daytime. Using the formula reported by ISO 17166 the UV-Index was calculated for each of the different sun spectra. Subsequently spectral responsivity curve of seven different UV-Index-Radiometers (manufactured by sglux GmbH) was integrated with the 2073 different sun spectra (according to ISO 17166) and in total 14,511 different UV-Indices were calculated. The differences of spectral responsivity of the seven candidates result from inevitable production tolerances of the UV-Index-Radiometers. These 14,511 different UV-Indices obtained by the UV-Index- Radiometer were compared with the related UV-Indices calculated by the formula stated in ISO 17166.
As a result we could demonstrate that the spectral responsivity variance of the seven different UV-Index-Radiometers did not result a measurable influence on the measurement uncertainty. However, we saw an influence caused by the different sun spectra. In particular at extremely low UV-Indices of below 0.5 the measurement uncertainty increased. We saw that this measurement uncertainty follows a definable rule which allowed us to develop a gain matrix programmable into the radiometer’s firmware. After applying of this matrix the measurement uncertainty could be reduced down to ± 5 %, also for extremely low UV-Index values.
Accordingly, the study shows that the measurement uncertainty of the sglux UV-Index- radiometers is at the same level as reported from UV-Index-spectroradiometers. This result encourages to expand the investigation into the area of the UV-Index-Radiometers field of view (FOV). The ISO 17166 standard claims a FOV close to the cosine curve. If this FOV investigation would also result good results compared with UV-Index-Spectrometers one may regard the UV-Index-Radiometers as a reliable completion or even substitution of the spectroradiometers. This would create new opportunities to measure the UV-Index in regions where skilled personnel needed to maintain the spectroradiometers is not available.
¹Egli et al. Quality assessment of solar UV irradiance measured with array spectroradiometers, Atmos. Meas. Tech., 9, 1553–1567, 2016
Période: 2015
Numéro du projet: BMBF 03ZZ0109
Abstrait
Before starting this project no laboratory worldwide performed traceable calibration chains for mobile UV reference radiometers. Our work aimed at a scientific evaluation and completion of UV calibration chains realizing a PTB traceability. This goal was reached by systematic evaluation, improvement and completion of an existing measurement method. As a result we now present as the first laboratory worldwide a traceable calibration chain in the ultraviolet region. This new method will be applied by the members of the “advanced UV for life” project where the method serves to determine properties of the new products planned (mainly UV LED) by means of a traceable measurement. Furthermore, this new method will by applied by sglux to determine the properties of own products and products of third parties by means of calibration service.
Période: 2011-2013
Numéro du projet: BMWi ZIM EP 102409
Abstrait
A 128 pixel SiC UV spectrometer with a wavelength resolution of 2.3nm/pixel was development. The advantage of such kind of UV spectrometers result from the extreme radiation hardness and very high visible blindness of SiC compared with Si based UV spectrometers leading to zero stray light effects caused by visible light. This new spectrometer technology allows precise UV spectrometry in the presence of strong visible light such as UV measurements in the bright sun or under room light. Another advantage of the SiC based UV spectrometer results from the high radiation hardness and low dark current of this material. This features lead to a broader dynamic range of the spectrometer compared with conventional Si based spectrometers.
Période: 2010 – 2012
Numéro du projet: BMWi ZIM 2194602RR9
Abstrait
Processes like UV water purification or UV hardening require high intensity UV radiation where a traceable calibration did not exist. German sglux GmbH together with PTB (Physikalisch-Technische Bundesanstalt, German national metrology institute) developed the world’s first traceable calibration standard for high irradiation level, in particular for UV water purification sensor calibration
Publications
B. Barton¹, P. Sperfeld¹, A. Towara¹, G. Hopfenmueller²,
¹Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), 4.1 Photometry and Applied Radiometry, Braunschweig, Germany, ²sglux GmbH, Berlin, Germany
« Developing and setting up a calibration facility for UV sensors at high irradiance rates »
EMEA Regional Conference, Karlsruhe, Germany (2013)
P. Sperfeld¹, B. Barton¹, S. Pape¹, G. Hopfenmueller²,
¹Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), 4.1 Photometry and Applied Radiometry, Braunschweig, Germany, ²sglux GmbH, Berlin, Germany
« Traceable spectral irradiance measurements at UV water disinfection facilities »
EMEA Regional Conference, Karlsruhe, Germany (2013)
G. Hopfenmueller¹, T. Weiss¹, B. Barton², P. Sperfeld², S. Nowy², S. Pape², D. Friedrich², S. Winter², A. Towara², A. Hoepe², S. Teichert²,
¹sglux GmbH, Berlin, Germany, ²Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), 4.1 Photometry and Applied Radiometry, Braunschweig, Germany
« PTB traceable calibrated reference UV radiometer for measurements at high irradiance medium pressure mercury discharge lamps »
EMEA Regional Conference, Karlsruhe, Germany (2013)
P. Sperfeld¹, B. Barton¹, S. Pape¹, A. Towara¹, J. Eggers², G. Hopfenmueller³,
¹Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), Germany, ²DVGW-Technologiezentrum Wasser, Karlsruhe, Germany, ³sglux GmbH, Berlin, Germany
« Spectral irradiance measurement and actinic radiometer calibration for UV water disinfection »
Metrologia, issue 51 (2014), S. 282-288.
P. Sperfeld¹, B. Barton¹, S. Pape¹, A. Towara¹, J. Eggers², G. Hopfenmueller³,
¹Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), Germany, ²DVGW-Technologiezentrum Wasser, Karlsruhe, Germany, ³sglux GmbH, Berlin, Germany
« Spectral Irradiance Measurement and Actinic Radiometer Calibration for UV Water Disinfection »
Proceedings of NEWRAD 2014, edited by S. Park, P. Kaerhae and E. Ikonen. (Aalto University, Espoo, Finland 2014) p. 128.
Période: 2011
Numéro du projet: BMWi ZIM 2194602RR9
Abstrait
For monitoring high UV irradiance, silicon carbide (SiC) based photodiodes are used. This project characterized novel SiC UV photodiodes in terms of their spectral and integral responsivity. Special attention was paid to the aging behavior of the photodiodes due to high UV irradiance. Artificial aging of the samples were performed by illumination with a high power medium pressure mercury discharge lamp. After burn in no degradation could be measured.
Publications
S. Nowy¹, B. Barton¹, S. Pape¹, P. Sperfeld¹, D. Friedrich¹, S. Winter¹, G. Hopfenmueller², T. Weiss²,
¹Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), 4.1 Photometry and Applied Radiometry, Braunschweig, Germany, ²sglux GmbH, Berlin, Germany
« Characterisation of SiC photodiodes for high irradiance UV radiometers »
Proceedings of NEWRAD2011, edited by S. Park and E. Ikonen. (Aalto University, Espoo, Finland, 2011) p. 203.
Période: 2011
Numéro du projet: BMWi ZIM 2194602RR9
Abstrait
A detailed study of different properties of UV diffusers was performed. Diffusers are essential components of UV radiometers used as transfer standards. They improve the insensitivity to differing radiation situations.
Publications
Barton¹, B., Sperfeld¹, P., Nowy¹, S., Towara¹, A., Hoepe¹, A., Teichert¹, S., Hopfenmueller², G., Baer³, M. and Kreuzberger³, T.
¹Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), 4.1 Photometry and Applied Radiometry, Braunschweig, Germany, ²sglux GmbH, Berlin, Germany, ³SGIL Silicaglas GmbH, Langewiesen, Germany
« Characterisation of new optical diffusers used in high irradiance UV radiometers »
Proceedings of NEWRAD2011, edited by S. Park and E. Ikonen. (Aalto University, Espoo, Finland, 2011) p. 278.
Période: 2008- 2010
Numéro du projet: BMWi ZIM 2194601DB9
Abstrait
Highly efficient polytype 4H silicon carbide (4H-SiC) p–n diodes for ultraviolet (UV) light detection have been fabricated, characterized, and exposed to high-intensity mercury lamp irradiation (up to 17 mW/cm²). The behavior of the photocurrent response under UV light irradiation using a low-pressure mercury UV-C lamp (4 mW/cm²) and a medium-pressure mercury discharge lamp (17 mW/cm²) has been studied. Long-term UV photoaging tests had been performed for up to 22 months. Results demonstrate the robustness of SiC photodiodes against UV radiation. The devices under test showed an initial burn-in effect, i.e., the photocurrent response dropped by less than 5% within the first 40 h of artificial UV aging. Such burn-in effect under UV stress was also observed for previously available polytype 6H silicon carbide (6H–SiC) p–n photodetectors. After burn-in, no measurable degradation has been detected, which makes the devices excellent candidates for high irradiance UV detector applications.
Publications
D. Prasai¹, W. John¹, L. Weixelbaum¹, O. Krueger¹, G. Wagner², P. Sperfeld³, S. Nowy³, D. Friedrich³, S. Winter³ and T. Weiss⁴,
¹Ferdinand-Braun-Institut, Leibniz-Institut fuer Hoechstfrequenztechnik, Berlin, Germany, ²Leibniz-Institut fuer Kristallzuechtung, Berlin, Germany, ³Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), 4.1 Photometry and Applied Radiometry, Braunschweig, Germany, ⁴sglux GmbH, Berlin, Germany
« Highly reliable Silicon Carbide photodiodes for visible-blind ultraviolet detector applications »
J. Mater. Res., first view (2012).
Période: 2008-2009
Numéro du projet: BMBF 13N9586
Abstrait
Electronic and photoelectrical properties of semiconducting titanium dioxide layers had been investigated and improved.
Publications
C. Nitschke
« Electronic and photoelectrical properties of semiconducting titanium dioxide layers »
Beuth Hochschule für Technik, Master Thesis, 2009
¹sglux GmbH, Berlin, Germany, ²University of Freiberg, Germany
50th Annual Conference of the Radiation Protection Association 2018, Dresden, Germany
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Abstrait
Industrial application of ultraviolet radiation requires not only the evaluation of the effectiveness for the desired process but also an assessment of hazards for the operating personnel. Therefore rules and regulations have been established for the assessment and limitation of health-related threats. A variety of instruments are available on the market for this kind of risk assessment. These devices measure the radiation weighted according to applicable regulatory standards. But the final appraisal of risks such as maximum tolerable exposure time must still be computed manually afterwards.
The new approach presented here is based on a sensor with a spectral response characteristic tailored to a specific regulatory standard. This sensor is connected to a smart-phone. An application on the smart-phone will present the measurement value but also the maximum allowed exposure time in a graphical and acoustical manner. Each radiation source or regulatory guideline requires a specific sensor characteristic for an accurate risk assessment. Therefore the system extensively checks the requirements regarding the suitability of the connected sensor for the selected regulatory norm. These measures reduce the effort and the failure rate and also lower the burden for risk assessment in daily operation.
¹sglux GmbH, Berlin, Germany, ²University of Freiberg, Germany
50th Annual Conference of the Radiation Protection Association 2018, Dresden, Germany
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Abstrait
Environmental data are collected to improve health-related quality of life of citizens. The solar UV-Index provides a good indicator for reasonable sun protection measures and duration of sun light exposure for safety officers and individuals. In Germany the « Bundesamt für Strahlenschutz » manages a solar UV-measurement network to monitor the UV-Index. At ten sites distributed all over Germany spectroradiometers are operated to measure the solar spectrum. The spectroradiometers are expensive and need highly qualified personnel to be operated. Robust and low-maintenance SiC-based UV-Index-radiometers are a viable option to increase the density of this measurement network at low cost. The spectral sensitivity function of such UV-Index-radiometers must reproduce the erythemal action function according to ISO 17166 with high precision.
In this contribution we investigate the effect of production tolerances in the spectral response of SiC-based UV-Index-radiometer (SiC-UVI-radiometer) onto the precision of the measured UV-Index. This is performed by folding a large number of different sun spectra with a variety of spectral responses of actual SiC-UVI-radiometer and the erythemal action curve as defined in the ISO 17166. We can show that the measurement uncertainty of SiC-based UVI-radiometers is ±5 % and therefore in the range of spectroradiometers. We simulated UVI measurements for SiC-based UVI-radiometers with over 2000 different sun spectra and determined a discrepancy-correction-function, which allows a precise UVI-measurement.
sglux GmbH, Berlin, Germany
Abstrait
In this contribution we report about SiC based UV photodiodes as the core component of smart UV sensors for various medical applications. In dialysis machines the transparency of urea is monitored by a SiC UV photodiode based UV transmission measurement module. A photodiode combined with an optical filter which reproduces the erythermal action spectrum helps Lupus patients to monitor their daily dose of solar UV radiation. sglux UVC sensor “UV-Safester” is a smartphone based tool to detect harmful UV radiation at a workplace employing the ICNIRP regulation. A wireless UV sensor module monitors the UV disinfection applied by disinfection robots in operating rooms.
sglux GmbH, Berlin, Germany
International Conference on UV LED Technologies & Applications 2018, Berlin, Germany
Abstrait
Artificial UV radiation is applied in many processes such as UV disinfection, UV curing or biological activation. Besides discharge tubes, LEDs are becoming more important for a rising number of applications in particular UV curing or medical treatment. In general, exposure to UV radiation may cause health problems such as skin aging, eye damage or skin cancer. The potential danger varies with the irradiated wavelengths and the exposure time. The limits and the spectral weighting function of the UV irradiance are given in the directive 2006/25/EC published by the European Comission. The hereby submitted lecture will introduce a radiometer that precisely evaluates the hazard potential while displaying the maximum daily exposition time at a certain measurement point. The digital SiC based UV sensor has a spectral responsivity close to the biological weighting function and is calibrated to different UV LEDs with typical half widths. The sensor can be connected to any Android smartphone.
sglux GmbH, Berlin, Germany
Abstrait
In UV water purification applications UV sensors are monitoring the dosage of UV irradiation as according to ÖNORM and DVGW standards. sglux GmbH is manufacturing such sensors employing opaque synthetic quartz-glass diffusers as entrance windows. This paper investigates the influence of high-intensity UV irradiation on the transmission behavior of these diffusers. Quartz-glass and micro-porous quartz-glass were investigated. The sensors were continuously monitored while irradiated by a 1kW medium pressure Hg lamp with a total UV irradiance of 1000mW/cm² for 800 hours. Before and after the aging period the total transmissions of the diffusers were measured.
¹University of Veterinary Medicine, Unit of Physiology and Biophysics, Vienna, Austria, ²PMOD/WRC, Davos Dorf, Switzerland, ³Medical Univ. Innsbruck, Innsbruck, Austria, ⁴Royal Meteorological Institute of Belgium, Observations, Brussels, Belgium, ⁵Royal Belgian Institute for Space Aeronomy, Brussels, Belgium, ⁶Bulgarian Academy of Sciences, Stara Zagora, Bulgaria, ⁷Metorological and hydrological institute of Croatia, Metorological and hydrological institute of Croati, Croatia, ⁸Czech Hydrometeorological Institute, Solar and Ozone Department, Hradec Kralove, Czech Republic, ⁹Danish Meteorological Institute, Copenhagen, Denmark, ¹⁰Tartu Observatory, Tartumaa, Estonia, ¹¹Finnish Meteorological Institute, Helsinki, Finland, ¹²Météo-France, Toulouse Cedex, France, ¹³Bundesamt fur Strahlenschutz Neuherberg, Section for Optical Radiation, Neuherberg, Germany, ¹⁴sglux GmbH, Berlin, Germany, ¹⁵Aristotle University of Thessaloniki, Greece, ¹⁶Hungarian Meteorological Service, Marczell György Main Observatory, Budapest, Hungary, ¹⁷Sapienza Universita’ di Roma, Physics Department, Rome, Italy, ¹⁸ISPRA, Physical Agents Unit, Rome, Italy, ¹⁹ARPA Valle d’Aosta loc, Saint-Christophe, Italy, ²⁰LaMMA Consortium, Institute of Biometeorology of the National Research Council, Sesto Fiorentino, Italy, ²¹CNR-IBIMET, Florence, Italy, ²²ARPA di Vicenza, Vicenza, Italy, ²³National Research Council, Institute of Atmospheric Sciences and Climate, Bologna, Italy, ²⁴ENEA, Laboratory for Observations and Analyses of the Earth and Climate, Rome, Italy, ²⁵Lycée Classique de Diekirch, Computarium and meteoLCD, Diekirch, Luxembourg, ²⁶University of Malta, Institute for Sustainable Energy, Marsaxlokk, Malta, ²⁷Institute of Applied Physics of the Academy of Sciences of Moldova, Kishinev, Moldova (the Republic of), ²⁸Dutch National Health Institute (RIVM), Netherlands, ²⁹NILU – Norwegian Institute for Air Research, Kjeller, Norway, ³⁰University of Oslo, Institute of Physics, Oslo, Norway, ³¹Statens Stralevern, Monitoring and Research, Oesteras, Norway, ³²Institute of Meteorology and Water Management, Gdynia, Poland, ³³Institute of Geophysics, Polish Academy of Sciences, Warszw, Poland, ³⁴Instituto Português do Mar e da Atmosfera, Observatório Afonso Chaves, Ponta Delgada S. Miguel, Portugal, ³⁵Moscow State University, Moscow, Russian Federation, ³⁶University of Belgrade, Zemun, Serbia, ³⁷University of Novi Sad, Novi Sad, Serbia, ³⁸Slovenian Environment Agency, Ljubljana, Slovenia, ³⁹Slovakian Academy of Sciences, Tatranska Lomnica, Slovakia, ⁴⁰Spanish Meteorological Agency, Area of Atmospheric Observation Networks, Madrid, Spain, ⁴¹University of Valladolid, Valladolid, Spain, ⁴²National Institute for Aerospace Technology, Mazagon, Spain, ⁴³University of Extremadura, Department of Physics, Badajoz, Spain, ⁴⁴SMHI, Norköpping, Sweden, ⁴⁵MeteoSwiss, Atmospheric data division, Payerne, Switzerland, ⁴⁶University of Manchester, Manchester, United Kingdom of Great Britain and Northern Ireland, ⁴⁷Public Health England Centre for Radiation Chemical and Environmental Hazards, Radiation Dosimetry, Didcot, United Kingdom of Great Britain and Northern Ireland
Journal: Photochemical & Photobiological Sciences, Publisher: The Royal Society of Chemistry.
Abstrait
The UV Index was established more than 20 years ago as a tool for sun protection and health care. Shortly after its introduction, UV Index monitoring started in several countries either by newly acquired instruments or by converting measurements from existing instruments into the UV Index. The number of stations and networks has increased over the years. Currently, 160 stations in 25 European countries deliver online values to the public via the Internet. In this paper an overview of these UV Index monitoring sites in Europe is given. The overview includes instruments as well as quality assurance and quality control procedures. Furthermore, some examples are given about how UV Index values are presented to the public. Through these efforts, 57% of the European population is supplied with high quality information, enabling them to adapt behaviour. Although health care, including skin cancer prevention, is cost-effective, a proportion of the European population still doesn’t have access to UV Index information.
¹Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), Germany, ²DVGW-Technologiezentrum Wasser, Karlsruhe, Germany, ³sglux GmbH, Berlin, Germany
Metrologia, 51 (2014), S. 282-288.
Abstrait
In a joint project, sglux and PTB investigated and developed methods and equipment to measure the spectral and weighted irradiance of high-efficiency UV-C emitters used in water disinfection plants. A calibration facility was set up to calibrate the microbicidal irradiance responsivity of actinic radiometers with respect to the weighted spectral irradiance of specially selected low-pressure mercury and medium-pressure mercury UV lamps. To verify the calibration method and to perform on-site tests, spectral measurements were carried out directly at water disinfection plants in operation. The weighted microbicidal irradiance of the plants was calculated and compared to the measurements of various actinic radiometers.
¹Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), Germany, ²DVGW-Technologiezentrum Wasser, Karlsruhe, Germany, ³sglux GmbH, Berlin, Germany
Abstrait
In a joint project, sglux and PTB investigated and developed methods and equipment to measure the spectral and weighted irradiance of high-efficiency UV-C emitters used in water disinfection plants. A calibration facility was set up to calibrate the microbicidal irradiance responsivity of actinic radiometers with respect to the weighted spectral irradiance of specially selected Hg low-pressure and medium-pressure UV radiators. To verify the calibration and to perform on-site tests, spectral measurements have been carried out directly at water disinfection plants in operation. The weighted microbicidal irradiance of the plants was calculated and compared to the measurements of various actinic radiometers.
¹Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), 4.1 Photometry and Applied Radiometry, Braunschweig, Germany, ²sglux GmbH, Berlin, Germany
EMEA Regional Conference, Karlsruhe, Germany (2013)
Abstrait
PTB provides spectral irradiance calibrations traceable to national primary standards and the SI system. A transfer standard source for high UV irradiances has been constructed and characterized. A medium pressure Hg lamp and a low pressure Hg lamp provide different spectra at different irradiance levels. The system might serve as a calibration facility for DVGW & ÖNORM conform UV sensors. Calibration by direct substitution to reference sensors can be carried out.
¹Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), 4.1 Photometry and Applied Radiometry, Braunschweig, Germany, ²sglux GmbH, Berlin, Germany
EMEA Regional Conference, Karlsruhe, Germany (2013)
Abstrait
PTB provides spectral irradiance calibrations traceable to national primary standards and the SI system. Transportable spectroradiometer systems have been adapted for high UV irradiance measurements. Successful measurements at medium pressure Hg and low pressure Hg lamp facilities have been carried out. The effective microbicidal irradiances agree within 15%. 40° sensor geometry could be developed. Discussion about calibration service and support.
¹sglux GmbH, Berlin, Germany, ²Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), 4.1 Photometry and Applied Radiometry, Braunschweig, Germany
¹Ferdinand-Braun-Institut, Leibniz-Institut fuer Hoechstfrequenztechnik, Berlin, Germany, ²Leibniz-Institut fuer Kristallzuechtung, Berlin, Germany, ³Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), 4.1 Photometry and Applied Radiometry, Braunschweig, Germany, ⁴sglux GmbH, Berlin, Germany
J. Mater. Res., first view (2012).
Abstrait
Highly efficient polytype 4H silicon carbide (4H-SiC) p–n diodes for ultraviolet (UV) light detection have been fabricated, characterized, and exposed to high-intensity mercury lamp irradiation (up to 17 mW/cm²). The behavior of the photocurrent response under UV light irradiation using a low-pressure mercury UV-C lamp (4 mW/cm²) and a medium-pressure mercury discharge lamp (17 mW/cm²) has been studied. We report on long-term UV photoaging tests performed for up to 22 mo. Results demonstrate the robustness of SiC photodiodes against UV radiation. The devices under test showed an initial burn-in effect, i.e., the photocurrent response dropped by less than 5% within the first 40 h of artificial UV aging. Such burn-in effect under UV stress was also observed for previously available polytype 6H silicon carbide (6H–SiC) p–n photodetectors. After burn-in, no measurable degradation has been detected, which makes the devices excellent candidates for high irradiance UV detector applications.
¹Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), 4.1 Photometry and Applied Radiometry, Braunschweig, Germany, ²sglux GmbH, Berlin, Germany
Abstrait
For monitoring high UV irradiance, silicon carbide (SiC) based photodiodes are used. In this paper we describe the characterization of the novel SiC UV photodiodes in terms of their spectral and integral responsivity. Special attention is paid to the aging behavior of the photodiodes due to high UV irradiance. Artificial aging of the samples is performed by illumination with a high power medium pressure mercury discharge lamp.
¹Physikalisch-Technische Bundesanstalt Braunschweig und Berlin (PTB), 4.1 Photometry and Applied Radiometry, Braunschweig, Germany, ²sglux GmbH, Berlin, Germany, ³SGIL Silicaglas GmbH, Langewiesen, Germany
Abstrait
Diffusers are essential components of UV radiometers used as transfer standards. They improve the insensitivity to differing radiation situations. In combination with a beam limiting aperture, a diffuser defines the irradiated area [1]. A detailed study of different properties of UV diffusers is shown.
Beuth Hochschule für Technik, Master Thesis, 2009
Abstrait
In the present thesis electronic and photoelectrical properties of semiconducting titanium dioxide layers were measured using different measuring methods. The titanium dioxide layers had been produced using the sol-gel-process with different precursor solutions. The findings and insights gained shall be used to manipulate the structure and functionality of UV-photodiodes with titanium-dioxide-layers. Traps had been proven both by the analysis of the spectral resolution of the photocurrent and thermally stimulated luminescence. These traps are affected by the titanium dioxide-layer manufacturing process. Using the impedance spectroscopy, the UV-photodiodes inner structure, the width of the space charge layer and the electrical conduction of the titanium dioxide-layer grains and grain boundaries could be measured. Between the impedance of the UV-photodiodes and the speed of reaction a correlation could be noticed. Additionally voltage dependent current and capacity measurements had been carried out as well as thermally stimulated currents had been measured.
¹Hahn-Meitner-Institut, Berlin, Germany
²Department of Radiophysics, Taras Shevchenko University, Kyiv, Ukraine
³Bundesanstalt für Materialforschung, Berlin, Germany
⁴sglux GmbH, Berlin, Germany
JOURNAL OF APPLIED PHYSICS 98, 104501 (2005)
Abstrait
Pt/TiO2/Ti Schottky diodes were investigated by current-voltage analysis, photoresponse, and transient photocurrent(PC) in a wide temperature range. The compact TiO2 as well as the SiO2 passivation layers were prepared by the sol-gel technique. The Schottky-barrier height (1.2–1.3eV) was equal to the difference of the work functions of Pt and Ti. The temperature dependence of the ideality factor was interpreted in terms of a Gaussian distribution of barrier heights [J. H. Werner and H. H. Güttler, J. Appl. Phys.69, 1522 (1991)]. Space-charge-limited currents under the presence of defects with an exponential distribution were observed. Under zero-potential condition, the PC transients were practically independent of temperature and the electron drift mobility amounted to 2× 10E-4 cm² (Vs)
A screening dipole layer at the Pt/TiO2 junction was formed under low forward and reverse potentials. Defects were generated under electron injection.