Search

Low Gain Avalanche Diodes (LGADs) is one of the candidate sensing technologies for future 4D-tracking applications and recently have been qualified to be used in the ATLAS and CMS timing detectors for the CERN High Luminosity Large Hadron Collider upgrade. LGADs can achieve an excellent timing performance by the presence of an internal gain that improves the signal-to-noise ratio leading to a better time resolution. These detectors are designed to exhibit a moderate gain with an increase of the reverse bias voltage. The value of the gain strongly depends on the temperature. Thus, these two values must be kept under control in the experiments to maintain the gain within the required values. A reduction in the reverse bias or an increase in the temperature will reduce the gain significantly. In this paper, a mechanism for gain reduction in LGADs is going to be presented. It was observed, that the gain measured in these devices depends on the charge density projected into the gain layer, generated by a laser or a charged particle in their bulk. Measurements performed with different detectors showed that ionizing processes that induce more charge density in the detector bulk lead to a decrease in the detector’s measured gain. Measurements conducted with an IR-laser and a Sr-90 in the lab, modifying the charge density generated in the detector bulk, confirmed this mechanism and will be presented here.

This study analyzes the effects of the punch-through stop (PTS) layer and well depth in a bulk FinFET SRAM cell on the fraction of charge generated by an ion impact that is collected by the FinFET channel. More than 1700 3D TCAD simulations have been performed to obtain a detailed map of the sensitivity areas in a full cell 6-T SRAM 22 nm bulk-FinFET process. The influence of the well depth on the charge collected by the drain devices of the SRAM cell has been studied, and it has been concluded that the collected charge can be reduced down to 300% simply by modifying the depth of the well, without affecting the performance of the cell. Different PTS layer depths have been analyzed in order to calculate which value minimizes the impact of the charge generated by an ion during its track along the FinFET body. The simulations carried out allow to conclude that the incorporation of a PTS layer not only reduces the leakage current, but also reduces the amount of charge, delivered by the ion, that reaches the drain region. Simulation results also show that the fraction of the charge generated by the ion impact, which is collected by the drain, mainly depends on the depth of the wells, whereas the PTS layer hardly modifies the collected charge., Peer Reviewed, Postprint (published version)

The contact resistivity is a key parameter to reach high conversion efficiency in solar cells, especially in architectures based on the so-called carrier-selective contacts. The importance of contact resistivity relies on the evaluation of the quality of charge collection from the absorber bulk through adjacent electrodes. The electrode usually consists of a stack of layers entailing complex charge transport processes. This is especially the case of silicon heterojunction (SHJ) contacts. Although it is known that in thin-film silicon, the transport is based on subgap energy states, the mechanisms of charge collection in SHJ systems is not fully understood yet. Here, we analyse the physical mechanisms driving the exchange of charge among SHJ layers with the support of rigorous numerical simulations that reasonably replicate experimental results. We observe a connection between recombination and collection of carriers. Simulation results reveal that charge transport depends on the alignment and the nature of energy states at heterointerfaces. Our results demonstrate that transport based on direct energy transitions is more efficient than transport based on subgap energy states. Particularly, for positive charge collection, energy states associated to dangling bonds support the charge exchange more efficiently than tail states. The conditions for optimal carrier collection rely on the Fermi energy of the layers, in terms of activation energy of doped layers and carrier concentration of transparent conductive oxide. We observe that fill factor (FF) above 86% concurrently with 750-mV open circuit voltage can be attained in SHJ solar cells with ρc lower than 45 mΩ·cm2 for p-contact and 20 mΩ·cm2 for the n-contact. Furthermore, for achieving optimal contact resistivity, we provide engineering guidelines that are valid for a wide range of silicon materials from amorphous to nanocrystalline layers., Photovoltaic Materials and Devices, Electrical Sustainable Energy

In this paper, we present a new method to mitigate the effect of the charge collected by trigate FinFET devices after an ionizing particle impact. The method is based on the creation of an internal structure that generates an electrical field that drives the charge generated by the ion track out of the sensitive device terminals. This electrical field is generated with the insertion of complementary doped regions near the active region of the device. We analyze the influence of the distance of those regions to the device, their depth into the substrate and their doping concentration to determine the optimal implementation which minimizes the collected charge. The impact on the device performance in terms of leakage current, threshold voltage, maximum transconductance and subthreshold voltage swing has also been investigated. Our results show that the added structures introduce negligible effects in performance degradation and total leakage current, at the cost of a small increase in area. The simulations performed with technology computer-aided design numerical (TCAD) tools in 22nm bulk FinFET technology show that the amount of charge collected by the device terminals can be reduced up to 50% for a linear energy transfer (LET) of 60 MeV-cm2/mg., Peer Reviewed, Postprint (published version)

Pour réduire notre dépendance de combustibles fossiles et contrôler les émissions de gaz à effet de serre, il est nécessaire de passer à des sources d'énergie plus durables. Ce défi peut être relevé par les cellules solaires dites de troisième génération. Au cours de la dernière décennie, ces dispositifs se sont rapidement améliorés en matière d'efficacité de photoconversion et sont devenus l'une des alternatives les plus rentables par rapport aux cellules de silicium disponibles sur le marché, grâce à la disponibilité des matériaux et des processus de fabrication simples et peu coûteux. Cette thèse explore principalement les interactions entre les matériaux semi-conducteurs et comment leurs propriétés peuvent être contrôlées, en appliquant des modulations appropriées des interfaces des nanomatériaux. Plus précisément, ce travail se focalise sur l’étude de trois types de cellules solaires : à colorant (DSSC), à points quantiques (QDSC) et celles à perovskite (PSC) allons des études fondamentales de l'alignement énergétique de la bande et de la dynamique des porteurs dans les points quantiques de chalcogénure métallique composite (QD) jusqu'à la réalisation de dispositifs pleinement opérationnels, avec des couches d'interface modifiées afin de réduire la recombinaison porteuse et améliorer la collecte et donc le rendement final et la stabilité. Une nouvelle photo anode pour DSSC est présentée. Un composite de nanotubes de carbone fonctionnalisés à parois multiples (F-MWCNTs) et de TiO2 est utilisé comme photo anodes et le rôle du F-MWCNTS dans le transfert de charge sont étudiés. De l'autre côté, le film mince commun coûteux en Pt CE en DSSC est remplacé par un CE nanostructuré à faible coût fait de nanofibres creuses en Pt/Pd d'alliage sont proposées. Là CE produite est non seulement moins chère, mais aussi plus performante. En QDSC, la modulation de l'injection de charge peut être réalisée en choisissant correctement la composition des QDs. Cependant, on manque enc

著者人数: 15名, Accepted: 2016-11-08

Excessive energy consumption and aggravated environmental pollution has called for the utilization of clean energy for efficient and effective energy conversion and storage. Semiconducting titania thin films with fascinating optical, electrical and electrochemical properties have been intensively investigated as promising anode materials for thin film optoelectronic and photovoltaic devices. However, facile solution-processed techniques for the preparation of high-quality titania-based thin films have not been extensively explored. The focus of this thesis is to synthesise uniform thin films of various titania nanostructures on transparent conducting oxide substrates via a simple hydrothermal route in a cost-effective and highly controlled manner, and to apply them as electron transport layers (ETLs) in perovskite solar cells (PSCs). In the first research chapter, diverse TiO2 ETLs with different dimensionalities (i.e. 0D nanoparticles (TNP), 1D nanowires (TNW) and 2D nanosheets (TNS)) were hydrothermally grown on the transparent conducting oxide substrate by varying the organic solvent used. PSCs constructed using 1D TNW or 2D TNS yield enhanced photovoltaic performance compared to the 0D TNP counterparts. On one hand, the porous TNW or TNS network is beneficial to the infiltration of perovskite precursor. On the other hand, the electron transport and charge extraction at the TNW/perovskite or TNS/perovskite interfaces was facilitated, and thus reduced interfacial recombination loss. Employing a bilayered ETL film consisting of a self-assembled TiO2 blocking layer and a subsequent TNW active layer, produced PSC devices with a power conversion efficiency (PCE) exceeding 16%. Then, efforts were focused on optimizing the electric properties and exploring low-temperature processability of the TNW structure. In Chapter 3, a glucose-assisted self-assembly solvothermal protocol is developed to prepare electron-rich TNW thin films that exhibit enhanced electron mobility. P

The following studies were performed for the purpose of clarification of the influence of aerospace environments on the electronic components, and the limitations and problems in the use of civil components, which are necessary for the development of aerospace components. (1) In the study on the radioactive ray tolerance of the electronic components, necessary data for the elucidation of the fundamental mechanism on the total dose effect and the single event effect were obtained. (2) In the study on the improvement of reliability of electronic parts, basic data were obtained in order to establish an evaluation method of phenomena which control the reliability of electronic parts. Literature survey was also conducted. (3) With respect to the study on the technology of quality assurance of electronic parts, an evaluation method of the performance of electronic parts was studied, which is necessary especially when civil components are adopted for use in the spacecraft. (4) In the study on the evaluation of civil parts with respect to their applicability for use in the spacecraft, basic data were obtained for the latest parts and mounting techniques which are frequently employed in civil equipment. (5) Concerning the future parts, literature study was made on civil components that have a wide applicability in the future commercial equipment, and possibility of their adaptability to the spacecraft was considered. Necessary data for clarification of various phenomena, and for the establishment of evaluation methods were obtained., 宇宙用部品の開発に必要な、宇宙環境の部品への影響の解明および、民生部品を宇宙機に使用する場合の制限条件と問題点を明確にする目的で、次の研究を行った。(1)電子部品の耐放射線性についての研究においては、トータルドーズ効果およびシングルイベント効果について、基本的メカニズムを究明するために必要なデータを取得した。(2)電子部品の信頼性向上についての検討では、電子部品の信頼性を左右する現象について評価する手法を確立するために、基本データを取得した。また、文献調査を行った。(3)電子部品の品質保証技術の検討では、特に民生部品を含む電子部品を宇宙機に使用する場合に必要な、部品の性能を評価するための手法を研究した。(4)民生部品の宇宙適用性の評価においては、民生機器に多く使用されている最新部品や最新実装技術の、宇宙への適用可否を評価するために必要な基礎データを取得した。(5)将来部品については、将来民生機器へ多く使用される可能性がある部品について、文献調査を行い、宇宙機への適用可能性の有無を検討した。これらの研究の結果、現象解明および評価手法の確立に必要なデータを取得できた。

This paper presents 3-D simulation of angled strike heavy ion induced charge collection in Silicon-Germanium Heterojunction Bipolar Transistors (SiGe HBTs). We select several different striking angles at various typical ion strike positions. The charge collection mechanism for each terminal is identified based on analysis of the device structure and simulation results. Angled strike ions induced charge collection present complex situation. With the change of striking angle, the longer the length of the ions track in sensitive volume, the more charge is collected. STI will prevent a part of diffused charge that charge collection reduces., 形態: カラー図版あり, 著者人数: 11名, Physical characteristics: Original contains color illustrations, Number of authors: 11

This thesis describes the electrical and charge collection characteristics of the updated second generation and third generation silicon-on-insulator (SOI) microdosimeter and its application to space and other areas. A microdosimeter is an important device used to measure the linear energy transfer (LET) distribution of radiation interacting with a biological system or electronics. It is important to have a good measure of the dose equivalent for medical and occupational safety purposes. The accurate measurement of the relative biological effect (RBE) of radiation field in these situations requires this portable microdosimeter device with a sensitive volume of the micron scale, equivalent to the size to a biological cell. The Centre for Medical Radiation Physics (CMRP) at the University of Wollongong (UOW) has previously developed a SOI device capable of measuring the pattern of energy deposited in small sensitive volumes (SV) of biological cell size. Despite good results being achieved with this device in clinical and radiation protection studies, further improved performance could be achieved via revision of the design. Together with its collaborative partners CMRP has developed the updated secondgeneration SOI microdosimeter on p-type high resistivity SOI with a 3D cylindrical pn junction sensitive volume (SV), which reduces the chord length variance and supports a radial electric field. The surface above the region outside the SV is topped with an N+ guard electrode to reduce any collection of laterally diffused charge. Two designs were tested: one where a defined guard ring electrode surrounds each individual SV and another where the guard ring electrode is covering contiguously the regions between all SVs. Fabrication and preliminary testing of different versions of the device is being performed at the semiconductor nanofabrication facility at the University of New South Wales (UNSW) and testing with ionising radiation is underway at the Australian Nuclear Sci

High quantum efficiency is important in X-ray imaging applications. This means using high-Z sensor materials. Unfortunately many of these materials suffer from defects that cause non-ideal charge transport. In order to increase the understanding of these defects, we have mapped the 3D response of a number of defects in two 1 mm thick CdTe sensors with different pixel sizes (55 mu m and 110 mu m) using a monoenergetic microbeam at 79 keV. The sensors were bump bonded to Timepix read out chips. Data was collected in photon counting as well as time-over-thresholdmode. The time-over-thresholdmode is a very powerful tool to investigate charge transport properties and fluorescence in pixellated detectors since the signal from the charge that each photon deposits in each pixel can be analyzed. Results show distorted electrical field around the defects, indications of excess leakage current and large differences in behavior between electron collection and hole collection mode. The experiments were carried out on the Extreme Conditions Beamline I15 at Diamond Light Source.

This thesis describes the electrical and charge collection characteristics of the updated second generation and third generation silicon-on-insulator (SOI) microdosimeter and its application to space and other areas. A microdosimeter is an important device used to measure the linear energy transfer (LET) distribution of radiation interacting with a biological system or electronics. It is important to have a good measure of the dose equivalent for medical and occupational safety purposes. The accurate measurement of the relative biological effect (RBE) of radiation field in these situations requires this portable microdosimeter device with a sensitive volume of the micron scale, equivalent to the size to a biological cell. The Centre for Medical Radiation Physics (CMRP) at the University of Wollongong (UOW) has previously developed a SOI device capable of measuring the pattern of energy deposited in small sensitive volumes (SV) of biological cell size. Despite good results being achieved with this device in clinical and radiation protection studies, further improved performance could be achieved via revision of the design. Together with its collaborative partners CMRP has developed the updated secondgeneration SOI microdosimeter on p-type high resistivity SOI with a 3D cylindrical pn junction sensitive volume (SV), which reduces the chord length variance and supports a radial electric field. The surface above the region outside the SV is topped with an N+ guard electrode to reduce any collection of laterally diffused charge. Two designs were tested: one where a defined guard ring electrode surrounds each individual SV and another where the guard ring electrode is covering contiguously the regions between all SVs. Fabrication and preliminary testing of different versions of the device is being performed at the semiconductor nanofabrication facility at the University of New South Wales (UNSW) and testing with ionising radiation is underway at the Australian Nuclear Sci

This thesis describes the electrical and charge collection characteristics of the updated second generation and third generation silicon-on-insulator (SOI) microdosimeter and its application to space and other areas. A microdosimeter is an important device used to measure the linear energy transfer (LET) distribution of radiation interacting with a biological system or electronics. It is important to have a good measure of the dose equivalent for medical and occupational safety purposes. The accurate measurement of the relative biological effect (RBE) of radiation field in these situations requires this portable microdosimeter device with a sensitive volume of the micron scale, equivalent to the size to a biological cell. The Centre for Medical Radiation Physics (CMRP) at the University of Wollongong (UOW) has previously developed a SOI device capable of measuring the pattern of energy deposited in small sensitive volumes (SV) of biological cell size. Despite good results being achieved with this device in clinical and radiation protection studies, further improved performance could be achieved via revision of the design. Together with its collaborative partners CMRP has developed the updated secondgeneration SOI microdosimeter on p-type high resistivity SOI with a 3D cylindrical pn junction sensitive volume (SV), which reduces the chord length variance and supports a radial electric field. The surface above the region outside the SV is topped with an N+ guard electrode to reduce any collection of laterally diffused charge. Two designs were tested: one where a defined guard ring electrode surrounds each individual SV and another where the guard ring electrode is covering contiguously the regions between all SVs. Fabrication and preliminary testing of different versions of the device is being performed at the semiconductor nanofabrication facility at the University of New South Wales (UNSW) and testing with ionising radiation is underway at the Australian Nuclear Sci

Germanium detector arrays are needed for low-level counting facilities. The applications in such user facilities include the characterization of low-level radioactive samples. In addition, the same detector arrays can perform important fundamental physics measurements, including the search for rare-events like neutrino-less double-beta decay. Recently, relatively large detectors (approximately 700 g) having relatively small (approximately few mm) p+ contacts are being investigated as a possible detector basis for these detector arrays. A detector having a small, relatively low capacitance, p+ contact has been fabricated as a demonstration. The development and properties of the detector system are discussed., Published in Proceedings of Monitoring Research Review (30th): Ground-Based Nuclear Explosion Monitoring Technologies, Portsmouth, VA, 23-25 Sep 2008, p768-771, sponsored by the National Nuclear Security Administration (NNSA) and the Air Force Research Laboratory (AFRL). Prepared in collaboration with Pacific Northwest National Laboratory. The original document contains color images.

In this paper, we discuss the measurement of charge collection in irradiated silicon pixel sensors and the comparison with a detailed simulation. The simulation implements a model of radiation damage by including two defect levels with opposite charge states and trapping of charge carriers. The modeling proves that a doubly peaked electric field generated by the two defect levels is necessary to describe the data and excludes a description based on acceptor defects uniformly distributed across the sensor bulk. In addition, the dependence of trap concentrations upon fluence is established by comparing the measured and simulated profiles at several fluences and bias voltages. © 2006 Elsevier B.V. All rights reserved.

A new method for the extraction of the electric field in the bulk of heavily irradiated silicon pixel sensors is presented. It is based on the measurement of the Lorentz deflection and mobility of electrons as a function of depth. The measurements were made at the CERN H2 beam line, with the beam at a shallow angle with respect to the pixel sensor surface. The extracted electric field is used to simulate the charge collection and the Lorentz deflection in the pixel sensor. The simulated charge collection and the Lorentz deflection is in good agreement with the measurements both for non-irradiated and irradiated up to 1015 neq / cm2 sensors. © 2005 Elsevier B.V. All rights reserved.

A new method for the extraction of the electric field in the bulk of heavily irradiated silicon pixel sensors is presented. It is based on the measurement of the Lorentz deflection and mobility of electrons as a function of depth. The measurements were made at the CERN H2 beam line, with the beam at a shallow angle with respect to the pixel sensor surface. The extracted electric field is used to simulate the charge collection and the Lorentz deflection in the pixel sensor. The simulated charge collection and the Lorentz deflection is in good agreement with the measurements both for non-irradiated and irradiated up to 1015 neq / cm2 sensors. © 2005 Elsevier B.V. All rights reserved.

In this paper, we discuss the measurement of charge collection in irradiated silicon pixel sensors and the comparison with a detailed simulation. The simulation implements a model of radiation damage by including two defect levels with opposite charge states and trapping of charge carriers. The modeling proves that a doubly peaked electric field generated by the two defect levels is necessary to describe the data and excludes a description based on acceptor defects uniformly distributed across the sensor bulk. In addition, the dependence of trap concentrations upon fluence is established by comparing the measured and simulated profiles at several fluences and bias voltages. © 2006 Elsevier B.V. All rights reserved.

In this paper, we discuss the measurement of charge collection in irradiated silicon pixel sensors and the comparison with a detailed simulation. The simulation implements a model of radiation damage by including two defect levels with opposite charge states and trapping of charge carriers. The modeling proves that a doubly peaked electric field generated by the two defect levels is necessary to describe the data and excludes a description based on acceptor defects uniformly distributed across the sensor bulk. In addition, the dependence of trap concentrations upon fluence is established by comparing the measured and simulated profiles at several fluences and bias voltages. © 2006 Elsevier B.V. All rights reserved.

A new method for the extraction of the electric field in the bulk of heavily irradiated silicon pixel sensors is presented. It is based on the measurement of the Lorentz deflection and mobility of electrons as a function of depth. The measurements were made at the CERN H2 beam line, with the beam at a shallow angle with respect to the pixel sensor surface. The extracted electric field is used to simulate the charge collection and the Lorentz deflection in the pixel sensor. The simulated charge collection and the Lorentz deflection is in good agreement with the measurements both for non-irradiated and irradiated up to 1015 neq / cm2 sensors. © 2005 Elsevier B.V. All rights reserved.

The spectrometric characteristics of the detectors based on 4H-SiC using 4.8-7.7 MeV a-particles were determined. The Cr Schottky barriers with areas of 1x10(-2) cm(2) were performed by vacuum thermal evaporation on 4H-SiC epitaxial layers grown by chemical vapor deposition (CVD) with thickness 26 and 50 μ m. The concentrations of the uncompensated donors into CVD epitaxial layers were (6-10) x10(14) cm(-3), that allowed to develop a detector depletion region up to 30 μ m using reverse bias of 400 V. The energy resolution less than 20 keV (0.34%) for lines of 5.0-5.5 MeV was achieved that is twice as large of the resolution of high-precision Si-based detectors prepared on specialized technology. The maximum signal amplitude of 4H-SiC - detectors corresponding to the average electron-hole pair generation energy was found to be 7.70 eV., QC 20111012

We have demonstrated that hole-type gaseous detectors, GEMs and capillary plates, can operate up to 77 K. For example, a single capillary plate can operate at gains of above 103 in the entire temperature interval between 300 until 77 K. The same capillary plate combined with Csi photocathodes could operate perfectly well at gains (depending on gas mixtures) of 100-1000. Obtained results may open new fields of applications for capillary plates as detectors of UV light and charge particles at cryogenic temperatures: noble liquid TPCs, WIMP detectors or LXe scintillating calorimeters and cryogenic PETs., QC 20141212

This paper reports on the sensor R&D activity for the CMS pixel detector. Devices featuring several design and technology options have been irradiated up to a proton fluence1 of 1 × 1015 n eq/cm2 at the CERN PS. Afterward, they were bump bonded to unirradiated readout chips and tested using high energy pions in the H2 beam line of the CERN SPS. The readout chip allows a nonzero suppressed full analogue readout and therefore a good characterization of the sensors in terms of noise and charge collection properties. The position dependence of signal is presented and the differences between the two sensor options are discussed.

The tracking system of the CMS experiment, currently under construction at the Large Hadron Collider (LHC) at CERN (Geneva, Switzerland), will include a silicon pixel detector providing three spacial measurements in its final configuration for tracks produced in high-energy pp collisions. In this paper, we present the results of test beam measurements performed at CERN on irradiated silicon pixel sensors. Lorentz angle and charge collection efficiency were measured for two sensor designs and at various bias voltages. © 2004 Elsevier B.V. All rights reserved.

The tracking system of the CMS experiment, currently under construction at the Large Hadron Collider (LHC) at CERN (Geneva, Switzerland), will include a silicon pixel detector providing three spacial measurements in its final configuration for tracks produced in high-energy pp collisions. In this paper, we present the results of test beam measurements performed at CERN on irradiated silicon pixel sensors. Lorentz angle and charge collection efficiency were measured for two sensor designs and at various bias voltages. © 2004 Elsevier B.V. All rights reserved.

This paper reports on the sensor R&D activity for the CMS pixel detector. Devices featuring several design and technology options have been irradiated up to a proton fluence1 of 1 × 1015 n eq/cm2 at the CERN PS. Afterward, they were bump bonded to unirradiated readout chips and tested using high energy pions in the H2 beam line of the CERN SPS. The readout chip allows a nonzero suppressed full analogue readout and therefore a good characterization of the sensors in terms of noise and charge collection properties. The position dependence of signal is presented and the differences between the two sensor options are discussed.

The tracking system of the CMS experiment, currently under construction at the Large Hadron Collider (LHC) at CERN (Geneva, Switzerland), will include a silicon pixel detector providing three spacial measurements in its final configuration for tracks produced in high-energy pp collisions. In this paper, we present the results of test beam measurements performed at CERN on irradiated silicon pixel sensors. Lorentz angle and charge collection efficiency were measured for two sensor designs and at various bias voltages. © 2004 Elsevier B.V. All rights reserved.

This paper reports on the sensor R&D activity for the CMS pixel detector. Devices featuring several design and technology options have been irradiated up to a proton fluence1 of 1 × 1015 n eq/cm2 at the CERN PS. Afterward, they were bump bonded to unirradiated readout chips and tested using high energy pions in the H2 beam line of the CERN SPS. The readout chip allows a nonzero suppressed full analogue readout and therefore a good characterization of the sensors in terms of noise and charge collection properties. The position dependence of signal is presented and the differences between the two sensor options are discussed.

In this paper we report an experimental study of photocurrent mobility x lifetime products and free carrier lifetimes in CVD grown polycrystalline diamond of various qualities. The investigated samples are low impurity samples, nitrogen content similar to 10(15) cm(-3), with an average grain size ranging from 25 mum up to 110 mum. This large difference in average grain size makes it possible to distinguish effects due to Lifetime limiting trapping and recombination defect centers inside the grains from effects caused by defect centers at grain boundaries. At low carrier densities, < 10(13) cm(-3) the effective free carrier lifetime is in the sub-nanosecond to nanosecond range in all samples due to intra-grain trapping and recombination centers. At high carrier densities, > 10(13) cm(-3), the intra-grain centers becomes saturated and the effective lifetime becomes predominately given by carrier diffusion to and recombination at the defects related to the grain boundaries. Hence, the effective lifetime at high carrier densities is strongly related to the average grain size and increases up to several tens of nanoseconds, in samples with a large average grain size, whereas it remains in the nanosecond range for samples with small average grain size. In addition, we observe a lower mobility x lifetime product and decay constant with increasing nitrogen content, clearly showing the negative influence of nitrogen and nitrogen-related defects on these important material parameters.

Computer simulation results are reported on transistor design and single-event charge collection modeling of metal-semiconductor field effect transistors (MESFETs) fabricated in the Vitesse H-GaAsIII{reg_sign} process on Low Temperature grown (LT) GaAs epitaxial layers. Tradeoffs in Single Event Upset (SEU) immunity and transistor design are discussed. Effects due to active loads and diffusion barriers are examined.

Experiments in charge control on the AF/NASA P78-2 (SCATHA) satellite were conducted with a plasma/ion source in the inner magnetosphere. These experiments were monitored with plasma wave instruments capable of high temporal and frequency resolution in the 0-6 kHz frequency range. Ion gun experiments revealed two distinct classes of behavior. Nonneutralized ion beam operation at 1 mA, 1 kV resulted in arcing signatures (spiky in time, broad frequency range), coincident with induced satellite potentials of {minus}600 to {minus}900 V. This signature disappeared with the accelerating voltage was switched off or the beam was neutralized (at which time the satellite body approached potentials of a few volts). The signal is attributed to arcing between differentially charged surfaces. An additional feature was noted in the 100-kHz channel of the wave receiver. During emission of dense, low-energy plasma, a signal is generated which may be at the upper hybrid, or plasma frequency for the local plasma.

Práce pojednává o studiu struktur polovodivého křemíku. Popisuje vlastnosti tohoto prvku a vytvoření polovodiče typu P a N, dále se zabývá typy poruch krystalické mřížky. Zabývá se popisem metod sledování poruch v polovodiči, stanovení vlastností polovodičů tj. metodou EBIC, EBIV a CC, které jsou využívány k analýze polovodičových součástek a materiálů. Zjišťování vlastností křemíkových součástek probíhá pomoci generace nosičů náboje ve vzorku, vloženého do komory rastrovacího elektronového mikroskopu dopadajícími vyskoenergiovými elektrony a následným sběrem naindukovaného náboje na PN přechodu. Pomocí dat získaných metodou EBIC a CC byly vyhodnoceny difúzní délka a doba života elektronů., This thesis treats about semiconducting silicon structures. It describes the characteristics of the element and creation of P and N type of semiconductor and discusses about different types of faults in the crystal lattice. It deals with the description of methods for monitoring faults in semiconductor ie. determining the properties of semiconductors via EBIC, EBIV and CC methods, which are used for analysis of semiconductor devices and materials. Determining the properties of silicon components is being done by generation of charge carriers in the sample loaded in chamber of the scanning electron microscope by high energy electrons. Bellow the sample surface is being generated an electric charge which is being collected by probes. Using this data obtained by EBIC and CC were evaluated diffusion length and lifetime of electrons.

Práce pojednává o studiu struktur polovodivého křemíku. Popisuje vlastnosti tohoto prvku a vytvoření polovodiče typu P a N, dále se zabývá typy poruch krystalické mřížky. Zabývá se popisem metod sledování poruch v polovodiči, stanovení vlastností polovodičů tj. metodou EBIC, EBIV a CC, které jsou využívány k analýze polovodičových součástek a materiálů. Zjišťování vlastností křemíkových součástek probíhá pomoci generace nosičů náboje ve vzorku, vloženého do komory rastrovacího elektronového mikroskopu dopadajícími vyskoenergiovými elektrony a následným sběrem naindukovaného náboje na PN přechodu. Pomocí dat získaných metodou EBIC a CC byly vyhodnoceny difúzní délka a doba života elektronů., This thesis treats about semiconducting silicon structures. It describes the characteristics of the element and creation of P and N type of semiconductor and discusses about different types of faults in the crystal lattice. It deals with the description of methods for monitoring faults in semiconductor ie. determining the properties of semiconductors via EBIC, EBIV and CC methods, which are used for analysis of semiconductor devices and materials. Determining the properties of silicon components is being done by generation of charge carriers in the sample loaded in chamber of the scanning electron microscope by high energy electrons. Bellow the sample surface is being generated an electric charge which is being collected by probes. Using this data obtained by EBIC and CC were evaluated diffusion length and lifetime of electrons.

Práce pojednává o studiu struktur polovodivého křemíku. Popisuje vlastnosti tohoto prvku a vytvoření polovodiče typu P a N, dále se zabývá typy poruch krystalické mřížky. Zabývá se popisem metod sledování poruch v polovodiči, stanovení vlastností polovodičů tj. metodou EBIC, EBIV a CC, které jsou využívány k analýze polovodičových součástek a materiálů. Zjišťování vlastností křemíkových součástek probíhá pomoci generace nosičů náboje ve vzorku, vloženého do komory rastrovacího elektronového mikroskopu dopadajícími vyskoenergiovými elektrony a následným sběrem naindukovaného náboje na PN přechodu. Pomocí dat získaných metodou EBIC a CC byly vyhodnoceny difúzní délka a doba života elektronů., This thesis treats about semiconducting silicon structures. It describes the characteristics of the element and creation of P and N type of semiconductor and discusses about different types of faults in the crystal lattice. It deals with the description of methods for monitoring faults in semiconductor ie. determining the properties of semiconductors via EBIC, EBIV and CC methods, which are used for analysis of semiconductor devices and materials. Determining the properties of silicon components is being done by generation of charge carriers in the sample loaded in chamber of the scanning electron microscope by high energy electrons. Bellow the sample surface is being generated an electric charge which is being collected by probes. Using this data obtained by EBIC and CC were evaluated diffusion length and lifetime of electrons.

Práce pojednává o studiu struktur polovodivého křemíku. Popisuje vlastnosti tohoto prvku a vytvoření polovodiče typu P a N, dále se zabývá typy poruch krystalické mřížky. Zabývá se popisem metod sledování poruch v polovodiči, stanovení vlastností polovodičů tj. metodou EBIC, EBIV a CC, které jsou využívány k analýze polovodičových součástek a materiálů. Zjišťování vlastností křemíkových součástek probíhá pomoci generace nosičů náboje ve vzorku, vloženého do komory rastrovacího elektronového mikroskopu dopadajícími vyskoenergiovými elektrony a následným sběrem naindukovaného náboje na PN přechodu. Pomocí dat získaných metodou EBIC a CC byly vyhodnoceny difúzní délka a doba života elektronů., This thesis treats about semiconducting silicon structures. It describes the characteristics of the element and creation of P and N type of semiconductor and discusses about different types of faults in the crystal lattice. It deals with the description of methods for monitoring faults in semiconductor ie. determining the properties of semiconductors via EBIC, EBIV and CC methods, which are used for analysis of semiconductor devices and materials. Determining the properties of silicon components is being done by generation of charge carriers in the sample loaded in chamber of the scanning electron microscope by high energy electrons. Bellow the sample surface is being generated an electric charge which is being collected by probes. Using this data obtained by EBIC and CC were evaluated diffusion length and lifetime of electrons.

Práce pojednává o studiu struktur polovodivého křemíku. Popisuje vlastnosti tohoto prvku a vytvoření polovodiče typu P a N, dále se zabývá typy poruch krystalické mřížky. Zabývá se popisem metod sledování poruch v polovodiči, stanovení vlastností polovodičů tj. metodou EBIC, EBIV a CC, které jsou využívány k analýze polovodičových součástek a materiálů. Zjišťování vlastností křemíkových součástek probíhá pomoci generace nosičů náboje ve vzorku, vloženého do komory rastrovacího elektronového mikroskopu dopadajícími vyskoenergiovými elektrony a následným sběrem naindukovaného náboje na PN přechodu. Pomocí dat získaných metodou EBIC a CC byly vyhodnoceny difúzní délka a doba života elektronů., This thesis treats about semiconducting silicon structures. It describes the characteristics of the element and creation of P and N type of semiconductor and discusses about different types of faults in the crystal lattice. It deals with the description of methods for monitoring faults in semiconductor ie. determining the properties of semiconductors via EBIC, EBIV and CC methods, which are used for analysis of semiconductor devices and materials. Determining the properties of silicon components is being done by generation of charge carriers in the sample loaded in chamber of the scanning electron microscope by high energy electrons. Bellow the sample surface is being generated an electric charge which is being collected by probes. Using this data obtained by EBIC and CC were evaluated diffusion length and lifetime of electrons.

Práce pojednává o studiu struktur polovodivého křemíku. Popisuje vlastnosti tohoto prvku a vytvoření polovodiče typu P a N, dále se zabývá typy poruch krystalické mřížky. Zabývá se popisem metod sledování poruch v polovodiči, stanovení vlastností polovodičů tj. metodou EBIC, EBIV a CC, které jsou využívány k analýze polovodičových součástek a materiálů. Zjišťování vlastností křemíkových součástek probíhá pomoci generace nosičů náboje ve vzorku, vloženého do komory rastrovacího elektronového mikroskopu dopadajícími vyskoenergiovými elektrony a následným sběrem naindukovaného náboje na PN přechodu. Pomocí dat získaných metodou EBIC a CC byly vyhodnoceny difúzní délka a doba života elektronů., This thesis treats about semiconducting silicon structures. It describes the characteristics of the element and creation of P and N type of semiconductor and discusses about different types of faults in the crystal lattice. It deals with the description of methods for monitoring faults in semiconductor ie. determining the properties of semiconductors via EBIC, EBIV and CC methods, which are used for analysis of semiconductor devices and materials. Determining the properties of silicon components is being done by generation of charge carriers in the sample loaded in chamber of the scanning electron microscope by high energy electrons. Bellow the sample surface is being generated an electric charge which is being collected by probes. Using this data obtained by EBIC and CC were evaluated diffusion length and lifetime of electrons.