The Experts below are selected from a list of 19143 Experts worldwide ranked by ideXlab platform
Takeshi Go Tsuru - One of the best experts on this subject based on the ideXlab platform.
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development of on chip pattern processing in event driven soi piXel detector for X Ray Astronomy with background rejection purpose
Journal of Instrumentation, 2020Co-Authors: Ayaki Takeda, Takeshi Go Tsuru, Koji Mori, Y Nishioka, Masataka Yukumoto, Takahiro Hida, Yoshiaki Kanemaru, S Yonemura, K Mieda, Takaaki TanakaAbstract:This paper reports on the development of on-chip pattern processing in the event-driven silicon-on-insulator piXel detector for X-Ray Astronomy with background rejection purpose. X-Ray charge-coupled device (CCD) detectors, well-established piXel detectors used in this field, has proven that classification of detected events considering their spatial pattern is effective for particle background rejection. Based on the current architecture of our device and from the CCD images obtained in space, we first established a design concept and algorithm of the pattern processor to be implemented. Then, we developed a new device, including a prototype pattern-processing circuit. EXperiments using X-Ray and beta-Ray radioisotopes demonstrated that the pattern processor properly works as eXpected, and the particle background rejection is realized in an on-chip fashion. This function is useful, especially in a limited-resource system such as the CubeSat.
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spectroscopic performance improvement of soi piXel detector for X Ray Astronomy by introducing double soi structure
Journal of Instrumentation, 2020Co-Authors: Ayaki Takeda, Takeshi Go Tsuru, Takaaki Tanaka, Hiroyuki Uchida, Koji Mori, Yusuke Nishioka, Kohei Fukuda, Masataka Yukumoto, Takahiro Hida, Hideki HayashiAbstract:This paper reports the spectroscopic performance improvement of the silicon-on-insulator (SOI) piXel detector for X-Ray Astronomy, by introducing a double-SOI (D-SOI) structure. For applications in X-Ray astronomical observatories, we have been developing a series of monolithic active piXel sensors, named as "XRPIXs," based on SOI piXel technology. The D-SOI structure has an advantage that it can suppress a parasitic capacitance between the sensing node and the circuit layer, due to which the closed-loop gain cannot be increased in our conventional XRPIXs with a single-SOI (S-SOI) structure. Compared to the S-SOI XRPIX, the closed-loop gain is doubled in the D-SOI XRPIX. The readout noise is effectively lowered to 33% (16 e− (rms)), and the energy resolution at 6.4 keV is improved by a factor of 1.7 (290 eV in FWHM). The suppression of the parasitic capacitance is also quantitatively evaluated based on the results of capacitance eXtraction simulation from the layout. This evaluation provides design guidelines for further reduction of the readout noise.
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optical blocking performance of ccds developed for the X Ray Astronomy satellite Xrism
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2020Co-Authors: Hiroyuki Uchida, Hiroshi Nakajima, Takeshi Go Tsuru, Takaaki Tanaka, Yuki Amano, Hiromichi Okon, Hirofumi Noda, Kiyoshi Hayashida, Hironori Matsumoto, Maho HanaokaAbstract:Abstract We have been developing P-channel Charge-Coupled Devices (CCDs) for the upcoming X-Ray Astronomy Satellite XRISM, planned to be launched in 2021. While the basic design of the CCD camera (Soft X-Ray Imager: SXI) is almost the same as that of the lost Hitomi (ASTRO-H) observatory, we are planning to reduce the phenomenon of “light leakages” that is one of the largest problems recognized in Hitomi data. We adopted a double-layer optical blocking layer on the XRISM CCDs and also added an eXtra aluminum layer on the backside of them. We develop a newly designed test sample CCD and irradiate it with optical light to evaluate the optical blocking performance. As a result, light leakages are effectively reduced compared with that of the Hitomi CCDs. We thus conclude that the issue is solved by the new design and that the XRISM CCDs satisfy the mission requirement for the SXI.
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radiation damage effects on double soi piXel sensors for X Ray Astronomy
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2020Co-Authors: K Hagino, Takeshi Go Tsuru, Takaaki Tanaka, Takayoshi Kohmura, Kousuke Negishi, Kenji Oono, Keigo Yarita, Mitsuki Hayashida, Masatoshi Kitajima, Hiroyuki UchidaAbstract:Abstract The X-Ray SOI piXel sensor onboard the FORCE satellite will be placed in the low earth orbit and will consequently suffer from the radiation effects mainly caused by geomagnetically trapped cosmic-Ray protons. Based on previous studies on the effects of radiation on SOI piXel sensors, the positive charges trapped in the oXide layer significantly affect the performance of the sensor. To improve the radiation hardness of the SOI piXel sensors, we introduced a double-SOI (D-SOI) structure containing an additional middle Si layer in the oXide layer. The negative potential applied on the middle Si layer compensates for the radiation effects, due to the trapped positive charges. Although the radiation hardness of the D-SOI piXel sensors for applications in high-energy accelerators has been evaluated, radiation effects for astronomical application in the D-SOI sensors has not been evaluated thus far. To evaluate the radiation effects of the D-SOI sensor, we perform an irradiation eXperiment using a 6-MeV proton beam with a total dose of ∼ 5 krad , corresponding to a few tens of years of in-orbit operation. This eXperiment indicates an improvement in the radiation hardness of the X-Ray D-SOI devices. On using an irradiation of 5 krad on the D-SOI device, the energy resolution in the full-width half maXimum for the 5.9-keV X-Ray increases by 7 ± 2 % , and the chip output gain decreases by 0 . 35 ± 0 . 09 % . The physical mechanism of the gain degradation is also investigated; it is found that the gain degradation is caused by an increase in the parasitic capacitance due to the enlarged buried n-well.
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sub piXel response of double soi piXel sensors for X Ray Astronomy
Journal of Instrumentation, 2019Co-Authors: K Hagino, Takeshi Go Tsuru, Takayoshi Kohmura, Kazuho Kayama, Sodai Harada, T Tanaka, Kousuke Negishi, Kenji Oono, Keigo Yarita, Hideaki MatsumuraAbstract:We have been developing the X-Ray silicon-on-insulator (SOI) piXel sensor called XRPIX for future astrophysical satellites. XRPIX is a monolithic active piXel sensor consisting of a high-resistivity Si sensor, thin SiO2 insulator, and CMOS piXel circuits that utilize SOI technology. Since XRPIX is capable of event-driven readouts, it can achieve high timing resolution greater than ~10 μs, which enables low background observation by adopting the anti-coincidence technique. One of the major issues in the development of XRPIX is the electrical interference between the sensor layer and circuit layer, which causes nonuniform detection efficiency at the piXel boundaries. In order to reduce the interference, we introduce a Double-SOI (D-SOI) structure, in which a thin Si layer (middle Si) is added to the insulator layer of the SOI structure. In this structure, the middle Si layer works as an electrical shield to decouple the sensor layer and circuit layer. We measured the detector response of the XRPIX with D-SOI structure at KEK. We irradiated the X-Ray beam collimated with 4 μm pinhole, and scanned the device with 6 μm pitch, which is 1/6 of the piXel size. In this paper, we present the improvement in the uniformity of the detection efficiency in D-SOI sensors, and discuss the detailed X-Ray response and its physical origins.
Ayaki Takeda - One of the best experts on this subject based on the ideXlab platform.
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development of on chip pattern processing in event driven soi piXel detector for X Ray Astronomy with background rejection purpose
Journal of Instrumentation, 2020Co-Authors: Ayaki Takeda, Takeshi Go Tsuru, Koji Mori, Y Nishioka, Masataka Yukumoto, Takahiro Hida, Yoshiaki Kanemaru, S Yonemura, K Mieda, Takaaki TanakaAbstract:This paper reports on the development of on-chip pattern processing in the event-driven silicon-on-insulator piXel detector for X-Ray Astronomy with background rejection purpose. X-Ray charge-coupled device (CCD) detectors, well-established piXel detectors used in this field, has proven that classification of detected events considering their spatial pattern is effective for particle background rejection. Based on the current architecture of our device and from the CCD images obtained in space, we first established a design concept and algorithm of the pattern processor to be implemented. Then, we developed a new device, including a prototype pattern-processing circuit. EXperiments using X-Ray and beta-Ray radioisotopes demonstrated that the pattern processor properly works as eXpected, and the particle background rejection is realized in an on-chip fashion. This function is useful, especially in a limited-resource system such as the CubeSat.
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spectroscopic performance improvement of soi piXel detector for X Ray Astronomy by introducing double soi structure
Journal of Instrumentation, 2020Co-Authors: Ayaki Takeda, Takeshi Go Tsuru, Takaaki Tanaka, Hiroyuki Uchida, Koji Mori, Yusuke Nishioka, Kohei Fukuda, Masataka Yukumoto, Takahiro Hida, Hideki HayashiAbstract:This paper reports the spectroscopic performance improvement of the silicon-on-insulator (SOI) piXel detector for X-Ray Astronomy, by introducing a double-SOI (D-SOI) structure. For applications in X-Ray astronomical observatories, we have been developing a series of monolithic active piXel sensors, named as "XRPIXs," based on SOI piXel technology. The D-SOI structure has an advantage that it can suppress a parasitic capacitance between the sensing node and the circuit layer, due to which the closed-loop gain cannot be increased in our conventional XRPIXs with a single-SOI (S-SOI) structure. Compared to the S-SOI XRPIX, the closed-loop gain is doubled in the D-SOI XRPIX. The readout noise is effectively lowered to 33% (16 e− (rms)), and the energy resolution at 6.4 keV is improved by a factor of 1.7 (290 eV in FWHM). The suppression of the parasitic capacitance is also quantitatively evaluated based on the results of capacitance eXtraction simulation from the layout. This evaluation provides design guidelines for further reduction of the readout noise.
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performance of the silicon on insulator piXel sensor for X Ray Astronomy XrpiX6e equipped with pinned depleted diode structure
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2019Co-Authors: Sodai Harada, Takeshi Go Tsuru, Takaaki Tanaka, Ayaki Takeda, Hideaki Matsumura, Hiroyuki Uchida, Koji Mori, Hideki Hayashi, Katsuhiro Tachibana, Yusuke NishiokaAbstract:Abstract We have been developing event driven X-Ray Silicon-On-Insulator (SOI) piXel sensors, called “XRPIX”, for the neXt generation of X-Ray Astronomy satellites. XRPIX is a monolithic active piXel sensor, fabricated using the SOI CMOS technology, and is equipped with the so-called “Event-Driven readout”, which allows reading out only hit piXels by using the trigger circuit implemented in each piXel. The current version of XRPIX has lower spectral performance in the Event-Driven readout mode than in the Frame readout mode, which is due to the interference between the sensor layer and the circuit layer. The interference also lowers the gain. In order to suppress the interference, we developed a new device, “XRPIX6E” equipped with the Pinned Depleted Diode structure. A sufficiently highly-doped buried p-well is formed at the interface between the buried oXide layer and the sensor layer, and acts as a shield layer. XRPIX6E eXhibits improved spectral performances both in the Event-Driven readout mode and in the Frame readout mode in comparison to previous devices. The energy resolutions in full width at half maXimum at 6.4 keV are 236 ± 1 eV and 335 ± 4 eV in the Frame and Event-Driven readout modes, respectively. There are differences between the readout noise and the spectral performance in the two modes, which suggests that some mechanism still degrades the performance in the Event-Driven readout mode.
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performance of soi piXel sensors developed for X Ray Astronomy
Nuclear Science Symposium and Medical Imaging Conference, 2018Co-Authors: T Tanaka, Takeshi Go Tsuru, Ayaki Takeda, Hideaki Matsumura, Hiroyuki Uchida, Yuki Amano, Kazuho Kayama, Sodai Harada, Tomoyuki Okuno, Koji MoriAbstract:We have been developing monolithic active piXel sensors for X-Rays based on the silicon-on-insulator technology. Our device consists of a low-resistivity Si layer for readout CMOS electronics, a high-resistivity Si sensor layer, and a SiO 2 layer between them. This configuration allows us both high-speed readout circuits and a thick (on the order of 100 m) depletion layer in a monolithic device. Each piXel circuit contains a trigger output function, with which we can achieve a time resolution of ≲ 10 s. One of our key development items is improvement of the energy resolution. We recently fabricated a device named XRPIX6E, to which we introduced a pinned depleted diode (PDD) structure. The structure reduces the capacitance coupling between the sensing area in the sensor layer and the piXel circuit, which degrades the spectral performance. With XRPIX6E, we achieve an energy resolution of ~ 150 eV in full width at half maXimum for 6.4-keV X-Rays. In addition to the good energy resolution, a large imaging area is required for practical use. We developed and tested XRPIX5b, which has an imaging area size of 21.9 mm 13.8 mm and is the largest device that we ever fabricated. We successfully obtain X-Ray data from almost all the 608 384 piXels with high uniformity.
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performance of soi piXel sensors developed for X Ray Astronomy
arXiv: Instrumentation and Methods for Astrophysics, 2018Co-Authors: T Tanaka, Takeshi Go Tsuru, Ayaki Takeda, Hideaki Matsumura, Hiroyuki Uchida, Yuki Amano, Kazuho Kayama, Sodai Harada, Tomoyuki Okuno, Koji MoriAbstract:We have been developing monolithic active piXel sensors for X-Rays based on the silicon-on-insulator technology. Our device consists of a low-resistivity Si layer for readout CMOS electronics, a high-resistivity Si sensor layer, and a SiO$_2$ layer between them. This configuration allows us both high-speed readout circuits and a thick (on the order of $100~\mu{\rm m}$) depletion layer in a monolithic device. Each piXel circuit contains a trigger output function, with which we can achieve a time resolution of $\lesssim 10~\mu{\rm s}$. One of our key development items is improvement of the energy resolution. We recently fabricated a device named XRPIX6E, to which we introduced a pinned depleted diode (PDD) structure. The structure reduces the capacitance coupling between the sensing area in the sensor layer and the piXel circuit, which degrades the spectral performance. With XRPIX6E, we achieve an energy resolution of $\sim 150$~eV in full width at half maXimum for 6.4-keV X-Rays. In addition to the good energy resolution, a large imaging area is required for practical use. We developed and tested XRPIX5b, which has an imaging area size of $21.9~{\rm mm} \times 13.8~{\rm mm}$ and is the largest device that we ever fabricated. We successfully obtain X-Ray data from almost all the $608 \times 384$ piXels with high uniformity.
Takaaki Tanaka - One of the best experts on this subject based on the ideXlab platform.
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development of on chip pattern processing in event driven soi piXel detector for X Ray Astronomy with background rejection purpose
Journal of Instrumentation, 2020Co-Authors: Ayaki Takeda, Takeshi Go Tsuru, Koji Mori, Y Nishioka, Masataka Yukumoto, Takahiro Hida, Yoshiaki Kanemaru, S Yonemura, K Mieda, Takaaki TanakaAbstract:This paper reports on the development of on-chip pattern processing in the event-driven silicon-on-insulator piXel detector for X-Ray Astronomy with background rejection purpose. X-Ray charge-coupled device (CCD) detectors, well-established piXel detectors used in this field, has proven that classification of detected events considering their spatial pattern is effective for particle background rejection. Based on the current architecture of our device and from the CCD images obtained in space, we first established a design concept and algorithm of the pattern processor to be implemented. Then, we developed a new device, including a prototype pattern-processing circuit. EXperiments using X-Ray and beta-Ray radioisotopes demonstrated that the pattern processor properly works as eXpected, and the particle background rejection is realized in an on-chip fashion. This function is useful, especially in a limited-resource system such as the CubeSat.
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spectroscopic performance improvement of soi piXel detector for X Ray Astronomy by introducing double soi structure
Journal of Instrumentation, 2020Co-Authors: Ayaki Takeda, Takeshi Go Tsuru, Takaaki Tanaka, Hiroyuki Uchida, Koji Mori, Yusuke Nishioka, Kohei Fukuda, Masataka Yukumoto, Takahiro Hida, Hideki HayashiAbstract:This paper reports the spectroscopic performance improvement of the silicon-on-insulator (SOI) piXel detector for X-Ray Astronomy, by introducing a double-SOI (D-SOI) structure. For applications in X-Ray astronomical observatories, we have been developing a series of monolithic active piXel sensors, named as "XRPIXs," based on SOI piXel technology. The D-SOI structure has an advantage that it can suppress a parasitic capacitance between the sensing node and the circuit layer, due to which the closed-loop gain cannot be increased in our conventional XRPIXs with a single-SOI (S-SOI) structure. Compared to the S-SOI XRPIX, the closed-loop gain is doubled in the D-SOI XRPIX. The readout noise is effectively lowered to 33% (16 e− (rms)), and the energy resolution at 6.4 keV is improved by a factor of 1.7 (290 eV in FWHM). The suppression of the parasitic capacitance is also quantitatively evaluated based on the results of capacitance eXtraction simulation from the layout. This evaluation provides design guidelines for further reduction of the readout noise.
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optical blocking performance of ccds developed for the X Ray Astronomy satellite Xrism
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2020Co-Authors: Hiroyuki Uchida, Hiroshi Nakajima, Takeshi Go Tsuru, Takaaki Tanaka, Yuki Amano, Hiromichi Okon, Hirofumi Noda, Kiyoshi Hayashida, Hironori Matsumoto, Maho HanaokaAbstract:Abstract We have been developing P-channel Charge-Coupled Devices (CCDs) for the upcoming X-Ray Astronomy Satellite XRISM, planned to be launched in 2021. While the basic design of the CCD camera (Soft X-Ray Imager: SXI) is almost the same as that of the lost Hitomi (ASTRO-H) observatory, we are planning to reduce the phenomenon of “light leakages” that is one of the largest problems recognized in Hitomi data. We adopted a double-layer optical blocking layer on the XRISM CCDs and also added an eXtra aluminum layer on the backside of them. We develop a newly designed test sample CCD and irradiate it with optical light to evaluate the optical blocking performance. As a result, light leakages are effectively reduced compared with that of the Hitomi CCDs. We thus conclude that the issue is solved by the new design and that the XRISM CCDs satisfy the mission requirement for the SXI.
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radiation damage effects on double soi piXel sensors for X Ray Astronomy
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2020Co-Authors: K Hagino, Takeshi Go Tsuru, Takaaki Tanaka, Takayoshi Kohmura, Kousuke Negishi, Kenji Oono, Keigo Yarita, Mitsuki Hayashida, Masatoshi Kitajima, Hiroyuki UchidaAbstract:Abstract The X-Ray SOI piXel sensor onboard the FORCE satellite will be placed in the low earth orbit and will consequently suffer from the radiation effects mainly caused by geomagnetically trapped cosmic-Ray protons. Based on previous studies on the effects of radiation on SOI piXel sensors, the positive charges trapped in the oXide layer significantly affect the performance of the sensor. To improve the radiation hardness of the SOI piXel sensors, we introduced a double-SOI (D-SOI) structure containing an additional middle Si layer in the oXide layer. The negative potential applied on the middle Si layer compensates for the radiation effects, due to the trapped positive charges. Although the radiation hardness of the D-SOI piXel sensors for applications in high-energy accelerators has been evaluated, radiation effects for astronomical application in the D-SOI sensors has not been evaluated thus far. To evaluate the radiation effects of the D-SOI sensor, we perform an irradiation eXperiment using a 6-MeV proton beam with a total dose of ∼ 5 krad , corresponding to a few tens of years of in-orbit operation. This eXperiment indicates an improvement in the radiation hardness of the X-Ray D-SOI devices. On using an irradiation of 5 krad on the D-SOI device, the energy resolution in the full-width half maXimum for the 5.9-keV X-Ray increases by 7 ± 2 % , and the chip output gain decreases by 0 . 35 ± 0 . 09 % . The physical mechanism of the gain degradation is also investigated; it is found that the gain degradation is caused by an increase in the parasitic capacitance due to the enlarged buried n-well.
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subpiXel response of soi piXel sensor for X Ray Astronomy with pinned depleted diode first result from mesh eXperiment
Journal of Instrumentation, 2019Co-Authors: Kazuho Kayama, Takeshi Go Tsuru, Takaaki Tanaka, Hiroyuki Uchida, Yuki Amano, Sodai Harada, Tomoyuki Okuno, Junko S Hiraga, Masayuki Yoshida, Yasuaki KamataAbstract:We have been developing a monolithic active piXel sensor, "XRPIX", for the Japan led future X-Ray Astronomy mission "FORCE" observing the X-Ray sky in the energy band of 1–80 keV with angular resolution of better than 15''. XRPIX is an upper part of a stack of two sensors of an imager system onboard FORCE, and covers the X-Ray energy band lower than 20 keV . The XRPIX device consists of a fully depleted high-resistivity silicon sensor layer for X-Ray detection, a low resistivity silicon layer for CMOS readout circuit, and a buried oXide layer in between, which is fabricated with 0.2 μm CMOS silicon-on-insulator (SOI) technology. Each piXel has a trigger circuit with which we can achieve a 10 μs time resolution, a few orders of magnitude higher than that with X-Ray Astronomy CCDs. We recently introduced a new type of a device structure, a pinned depleted diode (PDD), in the XRPIX device, and succeeded in improving the spectral performance, especially in a readout mode using the trigger function. In this paper, we apply a mesh eXperiment to the XRPIX devices for the first time in order to study the spectral response of the PDD device at the subpiXel resolution. We confirmed that the PDD structure solves the significant degradation of the charge collection efficiency at the piXel boundaries and in the region under the piXel circuits, which is found in the single SOI structure, the conventional type of the device structure. On the other hand, the spectral line profiles are skewed with low energy tails and the line peaks slightly shift near the piXel boundaries, which contribute to a degradation of the energy resolution.
Hiroyuki Uchida - One of the best experts on this subject based on the ideXlab platform.
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spectroscopic performance improvement of soi piXel detector for X Ray Astronomy by introducing double soi structure
Journal of Instrumentation, 2020Co-Authors: Ayaki Takeda, Takeshi Go Tsuru, Takaaki Tanaka, Hiroyuki Uchida, Koji Mori, Yusuke Nishioka, Kohei Fukuda, Masataka Yukumoto, Takahiro Hida, Hideki HayashiAbstract:This paper reports the spectroscopic performance improvement of the silicon-on-insulator (SOI) piXel detector for X-Ray Astronomy, by introducing a double-SOI (D-SOI) structure. For applications in X-Ray astronomical observatories, we have been developing a series of monolithic active piXel sensors, named as "XRPIXs," based on SOI piXel technology. The D-SOI structure has an advantage that it can suppress a parasitic capacitance between the sensing node and the circuit layer, due to which the closed-loop gain cannot be increased in our conventional XRPIXs with a single-SOI (S-SOI) structure. Compared to the S-SOI XRPIX, the closed-loop gain is doubled in the D-SOI XRPIX. The readout noise is effectively lowered to 33% (16 e− (rms)), and the energy resolution at 6.4 keV is improved by a factor of 1.7 (290 eV in FWHM). The suppression of the parasitic capacitance is also quantitatively evaluated based on the results of capacitance eXtraction simulation from the layout. This evaluation provides design guidelines for further reduction of the readout noise.
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optical blocking performance of ccds developed for the X Ray Astronomy satellite Xrism
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2020Co-Authors: Hiroyuki Uchida, Hiroshi Nakajima, Takeshi Go Tsuru, Takaaki Tanaka, Yuki Amano, Hiromichi Okon, Hirofumi Noda, Kiyoshi Hayashida, Hironori Matsumoto, Maho HanaokaAbstract:Abstract We have been developing P-channel Charge-Coupled Devices (CCDs) for the upcoming X-Ray Astronomy Satellite XRISM, planned to be launched in 2021. While the basic design of the CCD camera (Soft X-Ray Imager: SXI) is almost the same as that of the lost Hitomi (ASTRO-H) observatory, we are planning to reduce the phenomenon of “light leakages” that is one of the largest problems recognized in Hitomi data. We adopted a double-layer optical blocking layer on the XRISM CCDs and also added an eXtra aluminum layer on the backside of them. We develop a newly designed test sample CCD and irradiate it with optical light to evaluate the optical blocking performance. As a result, light leakages are effectively reduced compared with that of the Hitomi CCDs. We thus conclude that the issue is solved by the new design and that the XRISM CCDs satisfy the mission requirement for the SXI.
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radiation damage effects on double soi piXel sensors for X Ray Astronomy
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2020Co-Authors: K Hagino, Takeshi Go Tsuru, Takaaki Tanaka, Takayoshi Kohmura, Kousuke Negishi, Kenji Oono, Keigo Yarita, Mitsuki Hayashida, Masatoshi Kitajima, Hiroyuki UchidaAbstract:Abstract The X-Ray SOI piXel sensor onboard the FORCE satellite will be placed in the low earth orbit and will consequently suffer from the radiation effects mainly caused by geomagnetically trapped cosmic-Ray protons. Based on previous studies on the effects of radiation on SOI piXel sensors, the positive charges trapped in the oXide layer significantly affect the performance of the sensor. To improve the radiation hardness of the SOI piXel sensors, we introduced a double-SOI (D-SOI) structure containing an additional middle Si layer in the oXide layer. The negative potential applied on the middle Si layer compensates for the radiation effects, due to the trapped positive charges. Although the radiation hardness of the D-SOI piXel sensors for applications in high-energy accelerators has been evaluated, radiation effects for astronomical application in the D-SOI sensors has not been evaluated thus far. To evaluate the radiation effects of the D-SOI sensor, we perform an irradiation eXperiment using a 6-MeV proton beam with a total dose of ∼ 5 krad , corresponding to a few tens of years of in-orbit operation. This eXperiment indicates an improvement in the radiation hardness of the X-Ray D-SOI devices. On using an irradiation of 5 krad on the D-SOI device, the energy resolution in the full-width half maXimum for the 5.9-keV X-Ray increases by 7 ± 2 % , and the chip output gain decreases by 0 . 35 ± 0 . 09 % . The physical mechanism of the gain degradation is also investigated; it is found that the gain degradation is caused by an increase in the parasitic capacitance due to the enlarged buried n-well.
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subpiXel response of soi piXel sensor for X Ray Astronomy with pinned depleted diode first result from mesh eXperiment
Journal of Instrumentation, 2019Co-Authors: Kazuho Kayama, Takeshi Go Tsuru, Takaaki Tanaka, Hiroyuki Uchida, Yuki Amano, Sodai Harada, Tomoyuki Okuno, Junko S Hiraga, Masayuki Yoshida, Yasuaki KamataAbstract:We have been developing a monolithic active piXel sensor, "XRPIX", for the Japan led future X-Ray Astronomy mission "FORCE" observing the X-Ray sky in the energy band of 1–80 keV with angular resolution of better than 15''. XRPIX is an upper part of a stack of two sensors of an imager system onboard FORCE, and covers the X-Ray energy band lower than 20 keV . The XRPIX device consists of a fully depleted high-resistivity silicon sensor layer for X-Ray detection, a low resistivity silicon layer for CMOS readout circuit, and a buried oXide layer in between, which is fabricated with 0.2 μm CMOS silicon-on-insulator (SOI) technology. Each piXel has a trigger circuit with which we can achieve a 10 μs time resolution, a few orders of magnitude higher than that with X-Ray Astronomy CCDs. We recently introduced a new type of a device structure, a pinned depleted diode (PDD), in the XRPIX device, and succeeded in improving the spectral performance, especially in a readout mode using the trigger function. In this paper, we apply a mesh eXperiment to the XRPIX devices for the first time in order to study the spectral response of the PDD device at the subpiXel resolution. We confirmed that the PDD structure solves the significant degradation of the charge collection efficiency at the piXel boundaries and in the region under the piXel circuits, which is found in the single SOI structure, the conventional type of the device structure. On the other hand, the spectral line profiles are skewed with low energy tails and the line peaks slightly shift near the piXel boundaries, which contribute to a degradation of the energy resolution.
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performance of the silicon on insulator piXel sensor for X Ray Astronomy XrpiX6e equipped with pinned depleted diode structure
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2019Co-Authors: Sodai Harada, Takeshi Go Tsuru, Takaaki Tanaka, Ayaki Takeda, Hideaki Matsumura, Hiroyuki Uchida, Koji Mori, Hideki Hayashi, Katsuhiro Tachibana, Yusuke NishiokaAbstract:Abstract We have been developing event driven X-Ray Silicon-On-Insulator (SOI) piXel sensors, called “XRPIX”, for the neXt generation of X-Ray Astronomy satellites. XRPIX is a monolithic active piXel sensor, fabricated using the SOI CMOS technology, and is equipped with the so-called “Event-Driven readout”, which allows reading out only hit piXels by using the trigger circuit implemented in each piXel. The current version of XRPIX has lower spectral performance in the Event-Driven readout mode than in the Frame readout mode, which is due to the interference between the sensor layer and the circuit layer. The interference also lowers the gain. In order to suppress the interference, we developed a new device, “XRPIX6E” equipped with the Pinned Depleted Diode structure. A sufficiently highly-doped buried p-well is formed at the interface between the buried oXide layer and the sensor layer, and acts as a shield layer. XRPIX6E eXhibits improved spectral performances both in the Event-Driven readout mode and in the Frame readout mode in comparison to previous devices. The energy resolutions in full width at half maXimum at 6.4 keV are 236 ± 1 eV and 335 ± 4 eV in the Frame and Event-Driven readout modes, respectively. There are differences between the readout noise and the spectral performance in the two modes, which suggests that some mechanism still degrades the performance in the Event-Driven readout mode.
Koji Mori - One of the best experts on this subject based on the ideXlab platform.
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development of on chip pattern processing in event driven soi piXel detector for X Ray Astronomy with background rejection purpose
Journal of Instrumentation, 2020Co-Authors: Ayaki Takeda, Takeshi Go Tsuru, Koji Mori, Y Nishioka, Masataka Yukumoto, Takahiro Hida, Yoshiaki Kanemaru, S Yonemura, K Mieda, Takaaki TanakaAbstract:This paper reports on the development of on-chip pattern processing in the event-driven silicon-on-insulator piXel detector for X-Ray Astronomy with background rejection purpose. X-Ray charge-coupled device (CCD) detectors, well-established piXel detectors used in this field, has proven that classification of detected events considering their spatial pattern is effective for particle background rejection. Based on the current architecture of our device and from the CCD images obtained in space, we first established a design concept and algorithm of the pattern processor to be implemented. Then, we developed a new device, including a prototype pattern-processing circuit. EXperiments using X-Ray and beta-Ray radioisotopes demonstrated that the pattern processor properly works as eXpected, and the particle background rejection is realized in an on-chip fashion. This function is useful, especially in a limited-resource system such as the CubeSat.
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spectroscopic performance improvement of soi piXel detector for X Ray Astronomy by introducing double soi structure
Journal of Instrumentation, 2020Co-Authors: Ayaki Takeda, Takeshi Go Tsuru, Takaaki Tanaka, Hiroyuki Uchida, Koji Mori, Yusuke Nishioka, Kohei Fukuda, Masataka Yukumoto, Takahiro Hida, Hideki HayashiAbstract:This paper reports the spectroscopic performance improvement of the silicon-on-insulator (SOI) piXel detector for X-Ray Astronomy, by introducing a double-SOI (D-SOI) structure. For applications in X-Ray astronomical observatories, we have been developing a series of monolithic active piXel sensors, named as "XRPIXs," based on SOI piXel technology. The D-SOI structure has an advantage that it can suppress a parasitic capacitance between the sensing node and the circuit layer, due to which the closed-loop gain cannot be increased in our conventional XRPIXs with a single-SOI (S-SOI) structure. Compared to the S-SOI XRPIX, the closed-loop gain is doubled in the D-SOI XRPIX. The readout noise is effectively lowered to 33% (16 e− (rms)), and the energy resolution at 6.4 keV is improved by a factor of 1.7 (290 eV in FWHM). The suppression of the parasitic capacitance is also quantitatively evaluated based on the results of capacitance eXtraction simulation from the layout. This evaluation provides design guidelines for further reduction of the readout noise.
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performance of the silicon on insulator piXel sensor for X Ray Astronomy XrpiX6e equipped with pinned depleted diode structure
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2019Co-Authors: Sodai Harada, Takeshi Go Tsuru, Takaaki Tanaka, Ayaki Takeda, Hideaki Matsumura, Hiroyuki Uchida, Koji Mori, Hideki Hayashi, Katsuhiro Tachibana, Yusuke NishiokaAbstract:Abstract We have been developing event driven X-Ray Silicon-On-Insulator (SOI) piXel sensors, called “XRPIX”, for the neXt generation of X-Ray Astronomy satellites. XRPIX is a monolithic active piXel sensor, fabricated using the SOI CMOS technology, and is equipped with the so-called “Event-Driven readout”, which allows reading out only hit piXels by using the trigger circuit implemented in each piXel. The current version of XRPIX has lower spectral performance in the Event-Driven readout mode than in the Frame readout mode, which is due to the interference between the sensor layer and the circuit layer. The interference also lowers the gain. In order to suppress the interference, we developed a new device, “XRPIX6E” equipped with the Pinned Depleted Diode structure. A sufficiently highly-doped buried p-well is formed at the interface between the buried oXide layer and the sensor layer, and acts as a shield layer. XRPIX6E eXhibits improved spectral performances both in the Event-Driven readout mode and in the Frame readout mode in comparison to previous devices. The energy resolutions in full width at half maXimum at 6.4 keV are 236 ± 1 eV and 335 ± 4 eV in the Frame and Event-Driven readout modes, respectively. There are differences between the readout noise and the spectral performance in the two modes, which suggests that some mechanism still degrades the performance in the Event-Driven readout mode.
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performance of soi piXel sensors developed for X Ray Astronomy
Nuclear Science Symposium and Medical Imaging Conference, 2018Co-Authors: T Tanaka, Takeshi Go Tsuru, Ayaki Takeda, Hideaki Matsumura, Hiroyuki Uchida, Yuki Amano, Kazuho Kayama, Sodai Harada, Tomoyuki Okuno, Koji MoriAbstract:We have been developing monolithic active piXel sensors for X-Rays based on the silicon-on-insulator technology. Our device consists of a low-resistivity Si layer for readout CMOS electronics, a high-resistivity Si sensor layer, and a SiO 2 layer between them. This configuration allows us both high-speed readout circuits and a thick (on the order of 100 m) depletion layer in a monolithic device. Each piXel circuit contains a trigger output function, with which we can achieve a time resolution of ≲ 10 s. One of our key development items is improvement of the energy resolution. We recently fabricated a device named XRPIX6E, to which we introduced a pinned depleted diode (PDD) structure. The structure reduces the capacitance coupling between the sensing area in the sensor layer and the piXel circuit, which degrades the spectral performance. With XRPIX6E, we achieve an energy resolution of ~ 150 eV in full width at half maXimum for 6.4-keV X-Rays. In addition to the good energy resolution, a large imaging area is required for practical use. We developed and tested XRPIX5b, which has an imaging area size of 21.9 mm 13.8 mm and is the largest device that we ever fabricated. We successfully obtain X-Ray data from almost all the 608 384 piXels with high uniformity.
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performance of soi piXel sensors developed for X Ray Astronomy
arXiv: Instrumentation and Methods for Astrophysics, 2018Co-Authors: T Tanaka, Takeshi Go Tsuru, Ayaki Takeda, Hideaki Matsumura, Hiroyuki Uchida, Yuki Amano, Kazuho Kayama, Sodai Harada, Tomoyuki Okuno, Koji MoriAbstract:We have been developing monolithic active piXel sensors for X-Rays based on the silicon-on-insulator technology. Our device consists of a low-resistivity Si layer for readout CMOS electronics, a high-resistivity Si sensor layer, and a SiO$_2$ layer between them. This configuration allows us both high-speed readout circuits and a thick (on the order of $100~\mu{\rm m}$) depletion layer in a monolithic device. Each piXel circuit contains a trigger output function, with which we can achieve a time resolution of $\lesssim 10~\mu{\rm s}$. One of our key development items is improvement of the energy resolution. We recently fabricated a device named XRPIX6E, to which we introduced a pinned depleted diode (PDD) structure. The structure reduces the capacitance coupling between the sensing area in the sensor layer and the piXel circuit, which degrades the spectral performance. With XRPIX6E, we achieve an energy resolution of $\sim 150$~eV in full width at half maXimum for 6.4-keV X-Rays. In addition to the good energy resolution, a large imaging area is required for practical use. We developed and tested XRPIX5b, which has an imaging area size of $21.9~{\rm mm} \times 13.8~{\rm mm}$ and is the largest device that we ever fabricated. We successfully obtain X-Ray data from almost all the $608 \times 384$ piXels with high uniformity.
