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Rahman, H., An, S., Norlin, B., Fröjdh, C., Persson, E. & Engstrand, P. (2019). Maximized wood chip impregnation efficiency validated by new miniaturized X-ray fluorescence techniques. In: : . Paper presented at 11th Fundamental Mechanical Pulp Research Seminar, Norrköping, Sweden, April 2-4, 2019.
Open this publication in new window or tab >>Maximized wood chip impregnation efficiency validated by new miniaturized X-ray fluorescence techniques
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2019 (English)Conference paper, Oral presentation with published abstract (Refereed)
Abstract [en]

Manufacturing of chemi-thermomechanical pulp (CTMP) is increasing due to increased demand for packaging materials such as cardboard as well as tissue and other hygiene products. Today high yield pulp (HYP) is produced from different wood species. It is well-known that chip-refining is normally responsible for more than 60% of the electric energy consumption in most high yield pulping process. There are opportunities to improve energy efficiency and quality stability in defibration processes by means of optimizing impregnation. Impregnation is a key unit operation in CTMP production as well as in all chemical pulping and biorefinery systems. The efficiency of the impregnation is known to be crucial (Ferritsius et al. 1985; Gorski et al. 2010). Early research showed difficulties to achieve even distribution of sulphite and sodium ions in wood chips resulting in inhomogeneous fibre properties (Bengtsson et al. 1988). Increased and homogenous sulphonation leads to reduced shive content, which is a key factor in all end product applications. To address this issue developing a new type miniaturized X-ray based technique (XRF) to measure local concentration of sulphur and sodium across wood chips and in individual fibres could become a key tool.

 

The presence of elements as sulphur and sodium can be detected by X-ray fluorescence (XRF) or spectral absorption. At the XRF, images the surface of the sample using specific energies from K-shell or L-shell fluorescence. This method is investigated at the X-ray laboratory in Mid Sweden University research centre STC (Sensitive Things that Communicate) (Norlin et al. 2018). At the spectral absorption, images specific K-shell absorption energies in transmission X-ray images of the sample, a method widely used in medical diagnosis. This transmission method might also be further investigated for this application in the future (Frojdh et al. 2013; Reza et al. 2013). Both methods can be validated by using monoenergetic radiation from synchrotron facilities.

 

An XRF imaging system uses a collimated X-ray source and a spectroscopic detector. The sample is scanned to make an image of the content of the substances of interest. A specific challenge in this case is that the low energy fluorescence photons from sulphur (S) and sodium (Na) are easily absorbed in air, which makes imaging in a different atmosphere necessary.

 

The measurement setup has been simulated using MCNP (C. J. Werner, 2017) to validate the system setup and to select the correct, geometry, shielding, filtering and atmosphere for the measurement. The solution was to use a titanium box flooded with helium to minimise the absorption of fluorescence photons and to shield from scattered photons that might disturb the measurement, fig 1. A filter has been added to the X-ray source to make it nearly monoenergetic and to avoid emission of photons with energies close to the expected fluorescence. The system has been used to estimate sodium and sulphur content in low grammage handsheet (CTMP) or single wood chip samples. It is possible to build a laboratory instrument similar to the prototype setup to obtain the distribution of sodium and sulphur in XRF imaging.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 1: Photograph of XRF measurement setup with of moveable Helium atmosphere Ti box

However, the technique we are developing can become useful in mills to improve and control process efficiency, product properties and to find solutions to process problems in future. In addition, a more even distribution of the sulphonation can reduce specific energy demand in chip refining at certain shive content.

 

References

 

1.      Bengtsson, G., Simonson, R., Heitner, C., Beatson, R., and Ferguson, C. (1988): Chemimechanical pulping of birch wood chips, Part 2: Studies on impregnation of wood blocks using scanning electron microscopy and energy dispersive x-ray analysis, Nord. Pulp Paper Res. J. 3 (3), 132-138.

2.      C. J. Werner, (2017): MCNP User's manual, Code Version 6.2, Los Alamos National Laboratory report, LA-UR-17-29981.

3.      Ferritsius, O., and Moldenius, S. (1985): The effect of impregnation method on CTMP properties. In International Mechanical Pulping Conference Proceedings, SPCI, Stockholm (p. 91).

4.      Frojdh, C., Norlin, B. and Frojdh, E. (2013): Spectral X-ray imaging with single photon processing detectors, Journal of Instrumentaion, Volume 8, Article number C02010.  

5.      Gorski, D., Hill, J., Engstrand, P., and Johansson, L. (2010): Reduction of energy consumption in TMP refining through mechanical pre-treatment of wood chips, Nord. Pulp Paper Res. J, 25(2), 156-161.

6.      Norlin, B., Reza, S., Fröjdh, C. and Nordin, T. (2018): Precision scan-imaging for paperboard quality inspection utilizing X-ray fluorescence, Journal of Instrumentation, Volume: 13, Article number C01021.

7.      Reza, S., Norlin, B. and Thim, J. (2013): Non-destructive method to resolve the core and the coating on paperboard by spectroscopic x-ray imaging, Nord. Pulp Paper Res. J. 28 (3), 439-442.

 

Keywords
High Yield Pulp, XRF, CTMP
National Category
Engineering and Technology
Identifiers
urn:nbn:se:miun:diva-36216 (URN)978-91-88527-95-0 (ISBN)
Conference
11th Fundamental Mechanical Pulp Research Seminar, Norrköping, Sweden, April 2-4, 2019
Available from: 2019-05-28 Created: 2019-05-28 Last updated: 2019-05-29Bibliographically approved
Dreier, T., Krapohl, D., Maneuski, D., Lawal, N., Schöwerling, J. O., O'Shea, V. & Fröjdh, C. (2018). A USB 3.0 readout system for Timepix3 detectors with on-board processing capabilities. Paper presented at 20th International Workshop on Radiation Imaging Detectors, Sundsvall, Sweden, JUN 24-28, 2018. Journal of Instrumentation, 13, Article ID C11017.
Open this publication in new window or tab >>A USB 3.0 readout system for Timepix3 detectors with on-board processing capabilities
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2018 (English)In: Journal of Instrumentation, ISSN 1748-0221, E-ISSN 1748-0221, Vol. 13, article id C11017Article in journal (Refereed) Published
Abstract [en]

Timepix3 is a high-speed hybrid pixel detector consisting of a 256 x 256 pixel matrix with a maximum data rate of up to 5.12 Gbps (80 MHit/s). The ASIC is equipped with eight data channels that are data driven and zero suppressed making it suitable for particle tracking and spectral imaging.

In this paper, we present a USB 3.0-based programmable readout system with online preprocessing capabilities. USB 3.0 is present on all modern computers and can, under real-world conditions, achieve around 320MB/s, which allows up to 40 MHit/s of raw pixel data. With on-line processing, the proposed readout system is capable of achieving higher transfer rate (approaching Timepix4) since only relevant information rather than raw data will be transmitted. The system is based on an Opal Kelly development board with a Spartan 6 FPGA providing a USB 3.0 interface between FPGA and PC via an FX3 chip. It connects to a CERN T imepix 3 chipboard with standard VHDCI connector via a custom designed mezzanine card. The firmware is structured into blocks such as detector interface, USB interface and system control and an interface for data pre-processing. On the PC side, a Qt/C++ multi-platformsoftware library is implemented to control the readout system, providing access to detector functions and handling high-speed USB 3.0 streaming of data from the detector.

We demonstrate equalisation, calibration and data acquisition using a Cadmium Telluride sensor and optimise imaging data using simultaneous ToT (Time-over-Threshold) and ToA (Timeof- Arrival) information. The presented readout system is capable of other on-line processing such as analysis and classification of nuclear particles with current or larger FPGAs.

Keywords
Data processing methods, Detector control systems (detector and experiment monitoring and slow-control systems, architecture, hardware, algorithms, databases), Front-end electronics for detector readout, X-ray detectors
National Category
Accelerator Physics and Instrumentation
Identifiers
urn:nbn:se:miun:diva-34944 (URN)10.1088/1748-0221/13/11/C11017 (DOI)000450981800001 ()2-s2.0-85057630487 (Scopus ID)
Conference
20th International Workshop on Radiation Imaging Detectors, Sundsvall, Sweden, JUN 24-28, 2018
Available from: 2018-11-30 Created: 2018-11-30 Last updated: 2019-01-15Bibliographically approved
Thungström, G., Lundgren, A., Menk, R. H., Westerberg, L. & Fröjdh, C. (2018). Investigation of radiation hardness in lateral position sensitive detector, irradiated with 13.5 nm photons. Paper presented at 20th International Workshop on Radiation Imaging Detectors, Sundsvall, SWEDEN, JUN 24-28, 2018. Journal of Instrumentation, 13, Article ID C12015.
Open this publication in new window or tab >>Investigation of radiation hardness in lateral position sensitive detector, irradiated with 13.5 nm photons
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2018 (English)In: Journal of Instrumentation, ISSN 1748-0221, E-ISSN 1748-0221, Vol. 13, article id C12015Article in journal (Refereed) Published
Abstract [en]

Radiation hardness measurements have been done by irradiating lateral position sensitive (Si) detectors (LPSD) with 93 eV photons. Three different passivation layers have been investigated, SiO2, oxynitride and deposited 4 nm titanium-layer, on p in n-substrate LPSD and deposited 4 nm titanium layer on n in p-substrate LPSD. Best radiation hardness for 93 eV photon is obtained by using a 4 nm titanium layer. Only a slight decrease in response can be seen in the p in n-substrate LPSD. The best radiation hardness is achieved by using the n in p-substrate LPSD, which show no significant decrease in response. Scanning after irradiation with 93 eV gives only a variation in response of 0.26% in the surrounding area of exposure. No decrease in response can be detected during the scan. Test with a 108 eV photon beam gives an increased variation in response of 0.7%, caused by the shallower absorption in Si.

Keywords
Materials for solid-state detectors, Photon detectors for UV, visible and IR photons (vacuum), Radiation-hard detectors
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:miun:diva-35398 (URN)10.1088/1748-0221/13/12/C12015 (DOI)000453207800002 ()2-s2.0-85059896139 (Scopus ID)
Conference
20th International Workshop on Radiation Imaging Detectors, Sundsvall, SWEDEN, JUN 24-28, 2018
Available from: 2019-01-08 Created: 2019-01-08 Last updated: 2019-03-15Bibliographically approved
Norlin, B., Reza, S., Fröjdh, C. & Nordin, T. (2018). Precision scan-imaging for paperboard quality inspection utilizing X-ray fluorescence. Paper presented at 19th International Workshop on Radiation Imaging Detectors (IWORID2017), Krakow, Poland, 2-6 July, 2017. Journal of Instrumentation, 13(1), Article ID C01021.
Open this publication in new window or tab >>Precision scan-imaging for paperboard quality inspection utilizing X-ray fluorescence
2018 (English)In: Journal of Instrumentation, ISSN 1748-0221, E-ISSN 1748-0221, Vol. 13, no 1, article id C01021Article in journal (Refereed) Published
Abstract [en]

Paperboard is typically made up of a core of cellulose fibers [C6H10O5] and a coating layer of [CaCO3]. The uniformity of these layers is a critical parameter for the printing quality. Current quality control methods include chemistry based visual inspection methods as well as X-ray based methods to measure the coating thickness. In this work we combine the X-ray fluorescence signals from the Ca atoms (3.7 keV) in the coating and from a Cu target (8.0 keV) placed behind the paper to simultaneously measure both the coating and the fibers. Cu was selected as the target material since its fluorescence signal is well separated from the Ca signal while its fluorescence's still are absorbed sufficiently in the paper. A laboratory scale setup is built using stepper motors, a silicon drift detector based spectrometer and a collimated X-ray beam. The spectroscopic image is retrieved by scanning the paperboard surface and registering the fluorescence signals from Ca and Cu. The exposure time for this type of setups can be significantly improved by implementing spectroscopic imaging sensors. The material contents in the layers can then be retrieved from the absolute and relative intensities of these two signals.

National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:miun:diva-32724 (URN)10.1088/1748-0221/13/01/C01021 (DOI)000422899200004 ()2-s2.0-85041817589 (Scopus ID)
Conference
19th International Workshop on Radiation Imaging Detectors (IWORID2017), Krakow, Poland, 2-6 July, 2017
Available from: 2018-01-22 Created: 2018-01-22 Last updated: 2018-02-26Bibliographically approved
Norlin, B., Reza, S. & Fröjdh, C. (2017). X-ray fluorescence measurements of toxic metal content in ash from municipal solid waste incineration. In: 2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD): . Paper presented at 2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), Strasbourg, France, 29 Oct.-6 Nov. 2016. IEEE, 2017-January, Article ID 8069695.
Open this publication in new window or tab >>X-ray fluorescence measurements of toxic metal content in ash from municipal solid waste incineration
2017 (English)In: 2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), IEEE, 2017, Vol. 2017-January, article id 8069695Conference paper, Published paper (Refereed)
Abstract [en]

The vision of this paper is development of an online X-ray fluorescence method for monitoring of metal content in ash from municipal solid waste (MSW) incineration. With such measurements directly on site it is possible to optimize an ash washing process in incineration plants, allowing the fly ash to be stored in a landfill for non-hazardous waste. The presented X-ray fluorescence measurement assures that the measurement accuracy is sufficient for metal content monitoring. The actual measurement process is also fast enough to be possible to implement as an online measurement method. The optimal measurement setup is different for different metals. Several different metals might need environmental monitoring, which metals might vary over time due to systematic variations in waist content. Detection of a wide range of metals will require an X-ray source with variable voltage and multiple detectors.

Place, publisher, year, edition, pages
IEEE, 2017
National Category
Engineering and Technology
Identifiers
urn:nbn:se:miun:diva-31947 (URN)10.1109/NSSMIC.2016.8069695 (DOI)2-s2.0-85041723656 (Scopus ID)
Conference
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), Strasbourg, France, 29 Oct.-6 Nov. 2016
Available from: 2017-10-24 Created: 2017-10-24 Last updated: 2018-02-21Bibliographically approved
Fröjdh, C., Krapohl, D. & Thungström, G. (2016). Hard X-ray imaging and particle detection with TIMEPIX3. In: Proceedings of SPIE - The International Society for Optical Engineering: . Paper presented at SPIE Conference on Hard X-Ray, Gamma-Ray, and Neutron Detector Physics XVIII, AUG 29-31, 2016, San Diego, CA. SPIE - International Society for Optical Engineering, 9968, Article ID UNSP 99680T.
Open this publication in new window or tab >>Hard X-ray imaging and particle detection with TIMEPIX3
2016 (English)In: Proceedings of SPIE - The International Society for Optical Engineering, SPIE - International Society for Optical Engineering, 2016, Vol. 9968, article id UNSP 99680TConference paper, Published paper (Refereed)
Abstract [en]

CMOS pixel electronics open up for applications with single photon or particle processing. TIMEPIX3 is a readout chip in the MEDIPIX family with the ability to simultaneously determine energy and time of interaction in the pixel. The device is fully event driven, sending out data on each interaction at a maximum speed of about 40 Mhits/s. The concept allows for off-line processing to correct for charge sharing or to find the interaction point in multi pixel events. The timing resolution of 1.56 ns allows for three dimensional tracking of charged particles in a thick sensor due to the drift time for the charge in the sensor. The experiments in this presentation have been performed with silicon sensors bonded MEDIPIX family chips with special focus on TIMEPIX3. This presentation covers basic performance of the chip, spectral imaging with hard X-rays, detection and imaging with charged particles and neutrons. Cluster identification, centroiding and charge summing is extensively used to determine energy and position of the interaction. For neutron applications a converter layer was placed on top of the sensor.

Place, publisher, year, edition, pages
SPIE - International Society for Optical Engineering, 2016
Series
Proceedings of SPIE, ISSN 0277-786X ; 9968
Keywords
charge sharing, particle identification, Pixel detector, single photon processing
National Category
Physical Sciences
Identifiers
urn:nbn:se:miun:diva-29806 (URN)10.1117/12.2238505 (DOI)000389506700013 ()2-s2.0-85007206718 (Scopus ID)STC (Local ID)978-1-5106-0327-1 (ISBN)978-1-5106-0328-8 (ISBN)STC (Archive number)STC (OAI)
Conference
SPIE Conference on Hard X-Ray, Gamma-Ray, and Neutron Detector Physics XVIII, AUG 29-31, 2016, San Diego, CA
Available from: 2017-01-02 Created: 2017-01-02 Last updated: 2017-06-30Bibliographically approved
Krapohl, D., Schubel, A., Fröjdh, E., Thungström, G. & Fröjdh, C. (2016). Validation of Geant4 Pixel Detector Simulation Framework by Measurements with the Medipix Family Detectors. IEEE Transactions on Nuclear Science, 63(3), 1874-1881, Article ID 7497723.
Open this publication in new window or tab >>Validation of Geant4 Pixel Detector Simulation Framework by Measurements with the Medipix Family Detectors
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2016 (English)In: IEEE Transactions on Nuclear Science, ISSN 0018-9499, E-ISSN 1558-1578, Vol. 63, no 3, p. 1874-1881, article id 7497723Article in journal (Refereed) Published
Abstract [en]

Monte Carlo simulations are an extensively used tool for developingand understanding radiation detector systems. In this work, we usedresults of several chips and readout modes of the Medipix detector family to validatea Geant4 based pixel detector framework, developed in our group, thatis capable of simulating particle tracking, charge transport in thesensor material and different readout schemes. We experimentally verifiedthe simulation with different detector geometries in terms of pixelpitch and size as well as sensor material and sensor thickness. Thesingle pixel mode (SPM) and charge summing mode (CSM) in Medipix3 were evaluated with fluorescenceand synchrotron radiation. The integration of the charge sensitiveamplifier functionality in the simulation framework allowed to simulatethe time-over-threshold mode of the Timepix chip.Simulation and measurement have been compared in terms of spectralresolution using threshold scans in photon counting mode (Medipix3) and time over thresholdmode (Timepix). Furthercomparisons were done using X-ray tube spectra and beta decay to covera broad energy range. Additionally, TCAD simulations are performedas a comparison to a well-established simulation method. The resultsshow good agreement between simulation and measurement.

Keywords
Monte Carlo Simulation, Medipix, Timepix, photon counting detectors, x-ray, alpha-radiation
National Category
Accelerator Physics and Instrumentation
Identifiers
urn:nbn:se:miun:diva-27746 (URN)10.1109/TNS.2016.2555958 (DOI)000382463600021 ()2-s2.0-84978249235 (Scopus ID)STC (Local ID)STC (Archive number)STC (OAI)
Available from: 2016-05-20 Created: 2016-05-20 Last updated: 2017-06-30Bibliographically approved
Reza, S., Chang, H., Norlin, B., Fröjdh, C. & Thungström, G. (2015). Detecting Cr Contamination In Water Using X-Ray Fluorescence. In: 2015 IEEE Nuclear Science Symposium and Medical Imaging Conference: . Paper presented at 2015 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2015; San Diego; United States; 31 October 2015 through 7 November 2015. Institute of Electrical and Electronics Engineers (IEEE), Article ID 7581750.
Open this publication in new window or tab >>Detecting Cr Contamination In Water Using X-Ray Fluorescence
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2015 (English)In: 2015 IEEE Nuclear Science Symposium and Medical Imaging Conference, Institute of Electrical and Electronics Engineers (IEEE), 2015, article id 7581750Conference paper, Published paper (Other academic)
Abstract [en]

With the rapid growth in population and the overwhelming demand of industrial consumer products around the world, the amount of generated wastes is also increasing. Therefore, the optimal utilization of wastes and the waste management policies are very important in order to protect the environment[1]. The most common way of waste management is to dispose them into city dumps and landfills. These disposal sites may produce toxic and green house gases and also a substantial amount of leachate, which can affect the environment[2]. Leachate is liquid, which, while percolating through wastes in a landfill, extracts soluble and suspended solids. Leachate contains toxic and harmful substances, such as Chromium (Cr), Arsenic, Lead, Mercury, Benzene, Chloroform and Methylene Chloride, and can contaminate surface water and aquifers.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2015
National Category
Engineering and Technology Health Sciences Natural Sciences
Identifiers
urn:nbn:se:miun:diva-26295 (URN)10.1109/NSSMIC.2015.7581750 (DOI)2-s2.0-84994225825 (Scopus ID)STC (Local ID)STC (Archive number)STC (OAI)
Conference
2015 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2015; San Diego; United States; 31 October 2015 through 7 November 2015
Available from: 2015-11-24 Created: 2015-11-24 Last updated: 2017-03-02Bibliographically approved
Schübel, A., Krapohl, D., Fröjdh, E., Fröjdh, C. & Thungström, G. (2014). A Geant4 based framework for pixel detector simulation. Paper presented at 16th International Workshop on Radiation Imaging Detectors. Journal of Instrumentation, 9(12), Article ID C12018.
Open this publication in new window or tab >>A Geant4 based framework for pixel detector simulation
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2014 (English)In: Journal of Instrumentation, ISSN 1748-0221, E-ISSN 1748-0221, Vol. 9, no 12, article id C12018Article in journal (Refereed) Published
Abstract [en]

The output from a hybrid pixel detector depends on the interaction of the radiation with the sensor material, the transport of the resulting charge in the sensor, the pulse processing in the readout circuit and processing of the resulting signal. In order to understand the full behaviour of the device and to predict the performance of future devices it is important to have a framework that can simulate the entire process in the detector system.Geant4 is a Monte Carlo based toolkit for simulation of particle interaction with matter which is developed and actively used for CERN experiments and detector development [1]. By extending the Monte Carlo code in Geant4 with a charge carrier transport model of the sensor material and basic amplifier functionality as well as read out logic, a simulation of the complete detector system is possible.The MEDIPIX is a state of the art hybrid pixel detector that allows bonding of a wide range of sensor materials [2,3]. Simulation models have been developed and tested for different chips from the MEDIPIX family. The simulation is defined using configuration files to set the geometry, sensor material properties, number of pixels, pixel pitch and chip properties. Source properties as well as filters and objects in the beam can be added for different experimental set-ups. The interaction of radiation with the sensor is taken into account in the transport of the charge carriers in the sensor material and a current induced in the pixel electrode that triggers an amplifier response. Simulation results have been verified with X-ray fluorescence and radioactive sources using MEDIPIX family chips. In this paper we present the developed simulation framework and first results.

Keywords
Performance of high energy physics detectors, Simulation methods and programs, Software architectures (event data models, frameworks and databases)
National Category
Accelerator Physics and Instrumentation
Identifiers
urn:nbn:se:miun:diva-23708 (URN)10.1088/1748-0221/9/12/C12018 (DOI)000351342900002 ()2-s2.0-84918823479 (Scopus ID)STC (Local ID)STC (Archive number)STC (OAI)
Conference
16th International Workshop on Radiation Imaging Detectors
Available from: 2014-12-12 Created: 2014-12-12 Last updated: 2017-12-05Bibliographically approved
Thungström, G., Esebamen, O. X., Krapohl, D., Fröjdh, C., Nilsson, H.-E., Petersson, S. & Brenner, R. (2014). Fabrication, Characterization and Simulation of Channel Stop for n in p-Substrate Silicon Pixel Detectors. Journal of Instrumentation, 9(7), Art. no. C07013
Open this publication in new window or tab >>Fabrication, Characterization and Simulation of Channel Stop for n in p-Substrate Silicon Pixel Detectors
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2014 (English)In: Journal of Instrumentation, ISSN 1748-0221, E-ISSN 1748-0221, Vol. 9, no 7, p. Art. no. C07013-Article in journal (Refereed) Published
Abstract [en]

Silicon detectors made on p-substrates are expected to have a better radiation hardness as compared todetectors made on n-substrates. However, the fixed positive oxide charges induce an inversion layer ofelectrons in the substrate, which connects the pixels. The common means of solving this problem isby using a p-spray, individual p-stops or a combination of the two. Here, we investigate the use offield plates to suppress the fixed positive charges and to prevent the formation of an inversion layer.The fabricated detector shows a high breakdown voltage and low interpixel leakage current for astructure using biased field plates with a width of 20 μm. By using a spice model for simulation of thepreamplifier, a cross talk of about 1.6 % is achieved with this detector structure. The cross talk iscaused by capacitive and resistive coupling between the pixels

Keywords
Electronic detector readout concepts (solid-state), Radiation-hard detectors, Solid state detectors
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:miun:diva-22224 (URN)10.1088/1748-0221/9/07/C07013 (DOI)000340050700013 ()2-s2.0-84905165594 (Scopus ID)STC (Local ID)STC (Archive number)STC (OAI)
Available from: 2014-06-19 Created: 2014-06-19 Last updated: 2017-12-05Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-8325-5177

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