TY - RPRT A1 - Höller, Christoph A1 - Zeitler, Berndt A1 - Sabourin, Ivan T1 - Airborne and impact sound insulation data for cold-formed steel-framed walls and floors N2 - This report presents the results of an extensive series of direct sound insulation tests of cold-formed steel-framed walls and floors. The direct airborne sound insulation of 30 walls with cold-formed steel framing was measured in accordance with ASTM E90-09. The walls had steel studs with a depth of 92 mm (3-5/8”) or 152 mm (6”), and with a steel thickness of 1.09 mm (0.043”) or 1.37 mm (0.054”). Other parameters that were investigated included the number of layers and thickness of gypsum board, the cavity insulation, the stud spacing, and the use of resilient channels. The test results for some non-standard wall configurations that were tested for research purposes (e.g. for walls with gypsum board on one side only) are also included in this report. The direct airborne and impact sound insulation of 17 floors with cold-formed steel framing was measured in accordance with ASTM E90-09 and ASTM E492-09, respectively. The floors had steel joists with a depth of 254 mm (10”) or 317 mm (12.5”), and with a steel thickness of 1.37 mm (0.054”). The top surface of the floor/ceiling assemblies was composed of a corrugated steel deck with poured gypsum concrete, while the bottom surface was composed of a gypsum board ceiling on resilient channels. The influence of the joist depth and the number of layers and thickness of the ceiling gypsum board was investigated, as well as the influence of several floor coverings (e.g. laminate or carpet). The report presents the detailed specimen descriptions and specimen properties and the results from the standardized tests according to ASTM E90-09 and ASTM E492-09. Brief analyses of the parameters affecting the sound insulation of the steel-framed assemblies are provided. The tests presented in this report were part of a large research study that also included an investigation into the flanking sound transmission in cold-formed steel-framed buildings. The results of that study are described in the NRC Research Report RR-337, “Apparent Sound Insulation in Cold-Formed Steel-Framed Buildings” [1]. The NRC Research Report RR-337 also includes some of the airborne sound insulation results presented here, albeit without listing the detailed specimen descriptions and specimen properties that are provided in this report. Y1 - 2018 U6 - https://doi.org/10.4224/23002823 PB - National Research Council of Canada. Construction ER - TY - JOUR A1 - Höller, Christoph A1 - Gibbs, Barry M. T1 - Source substitution method for obtaining the power transmission from vibrating sources in buildings JF - Applied Acoustics N2 - This paper describes a method analogous to the airborne sound source substitution method, to estimate the vibrational power injected by a structure-borne sound source into the supporting building element. The injected vibrational power is required for prediction of the structure-borne sound pressure from vibrating equipment in buildings. The paper focuses on high-mobility sources connected to low-mobility receivers, a situation which is commonly encountered in heavyweight construction. The mobility mismatch simplifies the transformation of laboratory measurement data to prediction of transmitted power in-situ. Three case studies were performed. In the first study, the power injected by a simple test source into a resiliently supported aluminium plate was determined using direct and indirect methods. Source substitution was investigated with different calibration options: steady-state excitation, transient excitation, and spatial averaging. The source power could be determined within 4 dB, compared with direct measurements of the injected power. In the second study, the power injected by a second source into a concrete transmission suite floor was determined. The third study was of a combined heating and power unit on a masonry wall. In this study, a reference sound pressure level in a receiver room was calculated and compared with a criterion curve for the assessment of low-frequency noise complaints. The case studies demonstrate that structure-borne sound source substitution is a promising development of the reception plate method. While the latter can be used if a free reception plate is available, the former circumvents problems of determining the transmitted power into coupled plates and therefore has application to real building conditions. The use of the instrumented hammer for the calibration and the use of spatial averaging significantly simplify the method. Y1 - 2018 U6 - https://doi.org/10.1016/j.apacoust.2018.07.014 VL - 141 SP - 240 EP - 249 PB - Elsevier ER - TY - JOUR A1 - Lievens, Matthias A1 - Höller, Christoph A1 - Dietrich, Pascal A1 - Vorländer, Michael T1 - Predicting the Interaction Between Structure-Borne Sound Sources and Receiver Structures from Independently Measured Quantities BT - Case Study of a Washing Machine on a Wooden Joist Floor JF - Acta Acustica united with Acustica N2 - Structure-borne sound sources are usually characterised by their source activity and source mobility. By combining this data with the mobility of receiver structures it is theoretically possible to predict the sound pressure level in a building. In a case study of a washing machine on a wooden joist floor this prediction process was investigated. The prediction was based on the normal force component only. The contact area at the feet of the washing machine was made as small as possible to avoid the influence of moments while the in-plane components were assumed negligible. These conditions proved to allow for accurate predictions in the coupled state in a previous publication [1]. The results show that the prediction from independently measured normal source and receiver quantities yields large errors below 125 Hz as a consequence of the above assumption. Between 125 and 900 Hz the error of the prediction is within ± 5 dB. The case study further investigated two assumptions frequently encountered in practice: low and high-mobility sources and no cross-coupling between the feet Y1 - 2014 U6 - https://doi.org/10.3813/AAA.918688 VL - 100 IS - 1 SP - 79 EP - 92 PB - European Acoustics Association (EAA) ER - TY - RPRT A1 - Höller, Christoph A1 - Mahn, Jeffrey A1 - Quirt, David A1 - Schoenwald, Stefan A1 - Zeitler, Berndt T1 - Apparent sound insulation in cross-laminated timber buildings N2 - This Report presents the results from experimental studies of airborne sound transmission, together with an explanation of calculation procedures to predict the apparent airborne sound transmission between adjacent spaces in a building whose construction is based on cross-laminated timber (CLT) panels. There are several types of CLT constructions which are commercially available in Canada, but this study only focused on CLT panels that have adhesive between the faces of the timber elements in adjacent layers, but no adhesive bonding the adjacent timber elements within a given layer. There were noticeable gaps (up to 3 mm wide) between some of the timber elements comprising each layer of the CLT assembly. These CLT panels could be called “Face-Laminated CLT Panels” but are simply referred to as CLT panels in this Report. Another form of CLT panels has adhesive between the faces of the timber elements in adjacent layers as well as adhesive to bond the adjacent timber elements within a given layer. These are referred to as “Fully-Bonded CLT Panels” in this Report. Because fully-bonded CLT panels have different properties than face-laminated CLT panels, the sound transmission data and predictions in this Report do not apply to fully-bonded CLT panels. Y1 - 2017 U6 - https://doi.org/10.4224/23002009 PB - National Research Council of Canada. Construction ER - TY - JOUR A1 - Höller, Christoph A1 - Gibbs, Barry M. T1 - Indirect determination of the mobility of structure-borne sound sources JF - Journal of Sound and Vibration N2 - Methods are considered for the indirect determination of the mobility of structure-borne sound sources. Instead of performing measurements on the source in the free state, the source mobility is obtained from measurements made in-situ. This approach is beneficial if the source is difficult to suspend, or if it contains nonlinear structural elements. Two formulations for an indirect source mobility are derived theoretically. The first requires measurement of velocities at or near to the contact points. The second involves measurement of remote velocities only. Neither of the methods requires excitation at the contacts in the coupled state. Numerical simulations of coupled beams are used to validate the two methods and investigate their accuracy and reliability with respect to typical measurement errors, such as background noise and inaccuracies in sensor positioning. It is found that these can have a significant effect on the methods considered. Several experimental case studies with single-contact and multi-contact sources are performed. The results confirm the validity of the two methods in principle, but highlight their sensitivity to experimental errors. In a representative case study with a fan unit, average errors range between ±5 dB and ±10 dB, with occasional errors of up to 30 dB. Y1 - 2015 U6 - https://doi.org/10.1016/j.jsv.2015.01.011 VL - 344 SP - 38 EP - 58 PB - Elsevier ER - TY - JOUR A1 - Höller, Christoph A1 - Gibbs, Barry M. T1 - Inverse Method to Obtain Blocked Forces of Vibrating Sound Sources in Buildings JF - Acta Acustica united with Acustica N2 - Vibrating sources, such as building service equipment, are major contributors to noise in buildings. In order to predict and subsequently reduce the sound pressure levels generated by these devices, it is necessary to first predict the total vibrational power injected by them into the supporting building structure. Whilst simplified methods are available for the calculation of the total power through all contacts, it would be beneficial to have more detailed knowledge of the dominant contact powers. For sources on low-mobility building elements, the contact powers are determined by the blocked force, along with the real part of the receiver mobility at each contact. This paper describes a novel inverse method to obtain the blocked forces at each contact. The method employs an instrumented reception plate, which is numerically modelled to allow optimum accelerometer positions to be selected, for any source and any location. The underlying theory and measurement procedure are described, and experimental validations are presented. Y1 - 2017 U6 - https://doi.org/10.3813/AAA.919092 VL - 103 IS - 4 SP - 639 EP - 649 PB - ingenta ER - TY - RPRT A1 - Mahn, Jeffrey A1 - Quirt, David A1 - Höller, Christoph A1 - Müller-Trapet, Markus T1 - Addendum to RR-335: sound transmission through Nail-Laminated Timber (NLT) assemblies N2 - This report is published as an addendum to NRC Research Report RR-335 “Apparent Sound Insulation in Cross-Laminated Timber Buildings." It is intended that this addendum will be merged with RR-335 in the future as a report for predicting the sound insulation in buildings using mass-timber constructions including NLT assemblies. This report presents the results from experimental studies of airborne sound transmission through assemblies of nail-laminated timber (NLT) with various linings. To put the data presented in this report in the proper context, this report begins with a brief explanation of calculation procedures to predict the apparent sound transmission class (ASTC) between adjacent spaces in a building whose structure is a combination of mass-timber assemblies such as nail-laminated timber (NLT) or cross-laminated timber (CLT) panels. Y1 - 2018 U6 - https://doi.org/10.4224/40000417 PB - National Research Council of Canada. Construction ER - TY - RPRT A1 - Höller, Christoph A1 - Müller-Trapet, Markus A1 - King, Frances A1 - Bradley, John T1 - Evaluation of the communication performance of the C4 chemical, biological, radiological and nuclear mask N2 - The Canadian Armed Forces (CAF) are using chemical, biological, radiological and nuclear (CBRN) general service respirators (GSRs) to defend against CBRN threats and hazards to protect personnel and ensure that they can safely and successfully carry out missions. The CBRN GSR currently in use by the CAF is the C4 respirator. The National Research Council of Canada assessed the communication performance of the C4 respirator. This report presents the results of the performance test. The method for assessing the communication performance used in this study was the NIOSH standard test procedure TEB-CBRN-APR-STP-0313 [1]. Other methods exist to evaluate the communication performance of respirators, but historically the NIOSH standard test procedure has been used. This report details the implementation and results of the tests conducted at the National Research Council of Canada, following the NIOSH standard test procedure. Y1 - 2018 U6 - https://doi.org/10.4224/23003981 ER - TY - RPRT A1 - Höller, Christoph A1 - Quirt, David A1 - Zeitler, Berndt A1 - Sabourin, Ivan T1 - Apparent sound insulation in cold-formed steel-framed buildings N2 - This Report presents the results from substantial experimental studies of sound transmission, together with an explanation of calculation procedures to predict the sound transmission between adjacent spaces in a building whose walls and floors have cold-formed steel (CFS) framing. This first edition contains mainly data for loadbearing steel framing formed from sheet steel with thickness from 1.37 mm (16 gauge) to 0.94 mm (20 gauge). Non-loadbearing CFS studs formed from thinner steel (nominally 0.54 mm) are also commonly used but these are not included in the data tables for sound transmission through wall assemblies in this Report. KW - concrete block walls KW - floor KW - sound insulation KW - sound transmission Y1 - 2017 U6 - https://doi.org/10.4224/23001843 PB - National Research Council of Canada. Construction ER - TY - THES A1 - Höller, Christoph T1 - Indirect methods of obtaining activity and mobility of structure-borne sound sources N2 - The work reported in this thesis focuses on the development of indirect methods for the experimental determination of important source parameters for structure-borne sound source characterization. In the first part of the thesis, matrix inversion methods for the determination of blocked forces are investigated. A simplified measurement procedure is proposed which offers a solution to the two major challenges to these methods, namely the acquisition of the FRF matrix and the problems associated with matrix inversion. The proposed procedure involves a free, low-mobility receiver plate which is modelled numerically. Calculated FRFs are used together with measured velocity responses to inversely determine the blocked forces. It is found that while the method has great potential in principle, in practice the accurate modelling of the receiver plate is of critical importance. In the second part of the thesis, three formulations are considered for the indirect determination of source mobility. Instead of performing measurements on the source in the free state, the source mobility is obtained from measurements made in-situ. This approach is beneficial if the source is difficult to suspend, or if it contains non-linear structural elements. The three formulations are validated numerically and experimentally. It is found that the methods can quantify source mobilities of single-contact and multi-contact sources from in-situ measurements. However, typical measurement errors, such as background noise or inaccuracies in sensor positioning, can significantly reduce the accuracy and reliability of the methods. In the final part of the thesis, the reception plate method for the determination of the power injected by a high-mobility source into a low-mobility receiver is reviewed, and a source substitution method proposed as a development. The substitution method circumvents problems that may arise when the reception plate method is applied to coupled walls and floors. A special focus of investigation is on the calibration of the receiver structure. It is found that the calibration can be performed with shaker or hammer, and that an average calibration factor may be used. The source substitution method thus offers a potential alternative to the reception plate method, for application with coupled plates. Y1 - 2013 UR - https://livrepository.liverpool.ac.uk/id/eprint/14233 N1 - University of Liverpool, Dissertation PB - University of Liverpool CY - Liverpool ER - TY - JOUR A1 - Bauhuber, Michael A1 - Mikrievskij, Andreas A1 - Lechner, Alfred T1 - Isotropic wet chemical etching of deep channels with optical surface quality in silicon with HNA based etching solutions JF - Materials Science in Semiconductor Processing N2 - Online trace analysis based on UV/Vis spectroscopy requires long detection paths. Therefore an isotropic wet etch process in silicon is developed to fabricate a 300 µm deep channel with low channel wall roughness for desired light guidance application. Four etchant compositions were compared in terms of etching rate, surface roughness and selectivity in a beaker process. The best fitting mixture was selected. To further increase the surface quality (bubble issue) a spin etcher tool is used for producing the channels. The dependence of homogeneity and defect density on media flux, and rotation velocity was investigated. Results show that high rotation velocity and high media flux lead to great defects in the channel wall. Through rotation of the wafer during etching, the etching rate of silicon rises compared to the beaker process due to the rapid removal of etch products and simultaneous supply of fresh etchant. After 38 min of etching, 300 µm deep semi-circular channels with high optical quality (Rq=10 nm±2 nm) over 3 m were produced. Y1 - 2013 UR - https://www.scopus.com/authid/detail.uri?authorId=22980567700#disabled U6 - https://doi.org/10.1016/j.mssp.2013.05.017 VL - 16 IS - 6 SP - 1428 EP - 1433 PB - Elsevier ER - TY - CHAP A1 - Höller, Christoph A1 - Zeitler, Berndt T1 - Laboratory study on flanking sound transmission in cold-formed steel-framed constructions T2 - Towards a quieter future : 45th International Congress and Exposition on Noise Control Engineering (Internoise 2016) : Hamburg, Germany, 21-24 August 2016, Vol 8 N2 - In a recent study at the National Research Council Canada, the sound transmission in cold-formed steel-framed constructions was investigated. The results of direct sound insulation tests of wall and floor assemblies were reported at EURONOISE 2015 and INTERNOISE 2015. This paper focuses on flanking sound transmission in cold-formed steel-framed constructions. A representative full-scale mock-up specimen was constructed in NRC’s 8-room flanking transmission facility. The specimen consists of four loadbearing walls with 152 mm deep steel studs, four non-loadbearing walls with 92mm deep steel studs, and four floor-ceiling assemblies consisting of steel joists and a composite steel deck with gypsum concrete. Measurements were conducted according to the indirect method described in ISO 10848. The individual flanking paths were measured by a sequence of transmission loss measurements in which other transmission paths were suppressed by shielding. For the bare specimen without linings, the sound transmission for horizontally adjacent rooms with continuous subfloors is dominated by the floor-floor flanking paths. Floor coverings or floor toppings are needed to meet the requirements in the National Building Code of Canada. This paper presents details of the measurements, highlights some of the results and discusses implications. Y1 - 2016 UR - https://www.researchgate.net/publication/307210627_Laboratory_Study_on_Flanking_Sound_Transmission_in_Cold-Formed_Steel-Framed_Constructions SP - 6238 EP - 6249 PB - Curran Associates Inc. ER - TY - JOUR A1 - Hutterer, Albert A1 - Bauhuber, Michael A1 - Hummel, Helmut A1 - Lechner, Alfred T1 - Real-time analyses of metal contaminations in the ppb-range JF - Solid State Phenomena N2 - In high-tech processing even smallest concentrations of metal ions in process media are of the utmost significance because they cause expensive production failures. Currently, cost-intensive equipment, special trained staff and time consuming analyses are necessary to detect these contaminations in order to avoid failures. The Centers of Excellence Nanochem and Sensorics at the University of Applied Sciences Regensburg (owner of patent PCT/EP2010/064833) and their industrial partner Micro-Epsilon GmbH are developing a new miniaturized measurement device which allows cost-effective real-time analysis of fluidic media for the first time. The system is fully automated and can be directly connected to wet-etch benches. Hence it allows continuous real-time surveillance of metal contaminations in the ppb-range through absorption spectroscopy in process media. For this purpose a very small sample amount of the process medium and a specific complexing agent are mixed together. This leads to an increase in the molar extinction coefficients and though even smallest contaminations become visible. The main parts of our development are the simulation of the different system components, their production and chemical analyses with the evaluation model. KW - Absorption KW - Analysis KW - Complexing Agent KW - Light Guidance KW - Liquid-Core Waveguide KW - Metal Ions KW - Online Measurement KW - Real-Time KW - Total Internal Reflection Y1 - 2013 U6 - https://doi.org/10.4028/www.scientific.net/SSP.195 VL - 195 SP - 269 EP - 273 PB - Trans Tech Publications ER - TY - CHAP A1 - Höller, Christoph A1 - Zeitler, Berndt A1 - Mahn, Jeffrey T1 - Direct sound transmission loss of heavy gauge steel stud walls T2 - Proceedings of Euronoise 2015 : 10th European Congress and Exposition on Noise Control Engineering : Maastricht, 31 May - 3 June 2015 Y1 - 2015 SP - 1121 EP - 1126 CY - Maastricht ER - TY - JOUR A1 - Jungnitsch, Georg T1 - Psychotherapeutische Verfahren bei chronischen Schmerzen JF - Fortschritte der Medizin N2 - Psychotherapeutic possibilities of treating chronic pain are employed in two different ways: Firstly in the form of psychotherapy in patients whose strategies for coping with pain and/or pain genesis can be described in terms of psychopathological categories; secondly in the form of pain-coping training, which is generally indicated in the presence of chronic pain, in particular that which is traditionally termed organic. With respect to their effectiveness in achieving, in the first place, mood change, and in the assessment of symptoms, the individual procedures have been well tested. The question as to differential indication, which can most readily be applied to the use of biofeedback, remains largely unanswered. T2 - Psychotherapeutic possibilities of treating chronic pain Y1 - 1990 UR - https://www.researchgate.net/publication/292930409_Psychotherapeutic_possibilities_of_treating_chronic_pain VL - 108 IS - 8 SP - 50 EP - 58 ER - TY - JOUR A1 - Peter, Daniel A1 - Dalmer, Michael A1 - Lechner, Alfred A1 - Gigler, Alexander M. A1 - Stark, Robert W. A1 - Bensch, Wolfgang T1 - Measurement of the mechanical stability of semiconductor line structures in drying liquids with application to pattern collapse JF - Journal of Micromechanics and Microengineering N2 - Enhanced particle removal processes in wet cleaning as well as drying processes of semiconductor wafers can cause significant lateral forces on surface structures. These forces, however, must not exceed the mechanical stability of structures on the wafer. Thus, a mechanical fracture test was used to assess the lateral mechanical stability of polysilicon line structures in relevant process liquids. The mechanical test was based on nanomanipulation with an atomic force microscope. Compared to fracture tests in air, data acquired in liquid isopropanol revealed a stabilizing effect. The differences in fracture forces can be attributed to a stress corrosion process on the surface. The size of the generated damage was influenced by the viscosity of the surrounding media. Y1 - 2011 U6 - https://doi.org/10.1088/0960-1317/21/2/025001 VL - 21 IS - 2 PB - IOP Science ER - TY - CHAP A1 - Peter, Daniel A1 - Dalmer, Michael A1 - Lotnyk, Andriy A1 - Kienle, Lorenz A1 - Lechner, Alfred A1 - Bensch, Wolfgang T1 - Solid bridging during pattern collapse (stiction) studied on silicon nanoparticles T2 - MRS Online Proceedings Library N2 - The high surface to volume ratio of nanoparticles allows a detailed experimental study of the surface phenomena associated with solid bridging. Besides bulk analyses, the local view on the structure and composition via HRTEM is particularly essential. 50 nm core shell particles consisting of a silicon (Si) core and a SiO2 shell were used as model system to understand surface phenomena appearing for Si-based nanostructures. Evaporative drying from de-ionized water shows the most significant bridging effect based on SiO2. There is only a localized deposition of oxides between the particles during the drying process and no overall oxidation. For the deposition material, silicates are the most likely candidates. Y1 - 2011 U6 - https://doi.org/10.1557/opl.2011.397 VL - 1299 SP - 191 EP - 196 PB - Springer Nature ER - TY - CHAP A1 - Zeitler, Berndt A1 - Höller, Christoph A1 - Mahn, Jeffrey T1 - Empirical model of direct sound transmission through lightweight wood-framed construction T2 - Implementing noise control technology : 44th International Congress and Exposition on Noise Control Engineering (Internoise 2015) : San Francisco, California, USA, 9 - 12 August 2015 N2 - Tools to predict sound transmission through building elements are beneficial from both amarketing and a research standpoint. Prediction models can assist with the optimization ofelement performance and often reduce both cost and time in projects. However, the morephysical phenomena are to be included in the model, the more input data that is needed,which in some cases can be quite time-consuming and costly to collect. A balance is neededbetween the input and modeling effort and the output, which is usually delivered in onethird octave frequency bands or single number ratings. Many different types of models arecommonly used, including analytical, numerical, and empirical are used, all of which haveadvantages and disadvantages. In this paper, the latter type is presented using a set ofphysical properties of lightweight wood elements, and the errors made in the prediction arequantified. The disadvantage of empirical compared to analytical modeling is that thephysical phenomena are more difficult to identify. The advantage is often the simplicityand accuracy of the prediction results. Y1 - 2015 UR - https://www.researchgate.net/publication/281065914_Empirical_Model_of_Direct_Sound_Transmission_through_Lightweight_Wood-Framed_Construction PB - Curran CY - Red Hook, NY ER - TY - CHAP A1 - Zeitler, Berndt A1 - Mahn, Jeffrey A1 - Sabourin, Ivan A1 - Höller, Christoph A1 - Schoenwald, Stefan T1 - Apparent airborne sound insulation of hybrid wood-concrete masonry assemblies T2 - Euronoise 2015 : 10th European Congress and Exposition on Noise Control Engineering : Maastricht, 31 May - 3 June 2015 N2 - As part of a research project to develop design solutions for concrete-masonry buildings for the Canadian market, the apparent sound insulation performance of hybrid assemblies with concrete masonry walls and wood joist floors was evaluated. In this paper, the effect of junction coupling is investigated in an ISO 15712 flanking prediction context. Airborne flanking path data predicted according to ISO 15712 are compared to data measured using the indirect ISO 10848 shielding method. Recommendations are made on how appropriate the application of ISO 15712 is for this type of hybrid assembly. Y1 - 2015 UR - https://www.conforg.fr/euronoise2015/proceedings/data/articles/000436.pdf SP - 2515 EP - 2520 CY - Maastricht ER - TY - JOUR A1 - Dams, Florian A1 - Navitski, Aliaksandr A1 - Prommesberger, Christian A1 - Serbun, Pavel A1 - Langer, Christoph A1 - Müller, Günter A1 - Schreiner, Rupert T1 - Homogeneous Field Emission Cathodes With Precisely Adjustable Geometry Fabricated by Silicon Technology JF - IEEE Transactions on Electron Devices N2 - Silicon-based cathodes with precisely aligned field emitter arrays of sharp tips applicable for miniaturized electron sources were successfully fabricated and characterized. This was made possible by an improved fabrication process using wet thermal oxidation, wet etching, and reactive-ion etching steps with adjustable anisotropy. As substrate materials, both p-doped silicon and n-doped silicon were used. The cathode chips contain about 3 × 10 5 Si tips/cm 2 in a triangular array with tip heights of 2.5 μm, tip radii of less than 30 nm, and spacing of 20 μm. Well-aligned field emission (FE) and excellent homogeneity from all tips (i.e., 100% efficiency) and maximum stable currents of typically 0.1 μA (0.6 μA) for p (n)-type Si were reproducibly achieved. The current-voltage characteristics of the p-Si tips exhibit the expected saturation at around 10 nA with around ten times better current stability, whereas the n-Si tips show the usual Fowler-Nordheim behavior. Additional coating of the Si tips with 5-nm Cr and 10-nm Au layers resulted in improved stability and at least five times higher average FE current limits (about 3 μA) at about 30% higher operation voltage. KW - cathodes KW - electron field emission KW - elemental semiconductors KW - Field emission (FE) cathodes KW - field emitter array (FEA) KW - miniaturized electron sources KW - oxidation KW - silicon KW - silicon tips KW - sputter etching Y1 - 2012 U6 - https://doi.org/10.1109/TED.2012.2206598 SN - 0018-9383 SN - 1557-9646 VL - 59 IS - 10 SP - 2832 EP - 2837 PB - IEEE ER - TY - JOUR A1 - Tan, Pi Lin A1 - Yeap, Guan Yeow A1 - Chow, Wen Shyang A1 - Schreiner, Rupert A1 - Cheong, Kuan Yew T1 - Effect of Thickness of Porphyrin on Electrical Properties of Organic Devices JF - Advanced Materials Research (AMR) N2 - The study on electrical properties for both 2,3,7,8,12,13,17,18-octaethyl-21,23H-porphine Cu (II) (Cu-porphyrin) and 2,3,7,8,12,13,17,18-octaethyl-21,23H-porphine (porphyrin) thin film, which were fabricated using spin coating method was conducted. Porphyrins were diluted with chloroform of various concentrations (0.05 mg/ml, 0.1 mg/ml, 0.5 mg/ml, 2.0 mg/ml and 3.0 mg/ml). The solution was spin coated on top of glass substrates. A layer of aluminum was evaporated on top of the organic thin film through thermal evaporation and shadow mask was placed on top of the organic thin film where two electrodes with a gap of 50 μm were formed. Surface morphology of the organic thin film was observed by scanning electron microscope (SEM) and profilometer. Different concentrations of organic solutions greatly affected the molecular packing and arrangement order of the organic thin film and thickness of the organic layer and eventually affected electrical properties of the devices. KW - Porphyrin KW - Electrical Properties KW - Spin Coating Y1 - 2014 U6 - https://doi.org/10.4028/www.scientific.net/AMR.1024.381 SN - 1662-8985 SN - 1022-6680 VL - 1024 SP - 381 EP - 384 PB - Trans Tech Publications Ltd. CY - Baech ER - TY - JOUR A1 - Langer, Christoph A1 - Berndt, Dominik A1 - Schreiner, Rupert T1 - Sensitivity of thermal conductivity vacuum gauges for constant current and constant temperature operation JF - Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics N2 - To optimize the measurement range of thermal conductivity vacuum gauges, an expression for the sensitivity is required that takes into account all geometrical, material-specific, and operating parameters. Therefore, equations of the sensor output signal as a function of the pressure for the constant current and the constant temperature mode have been developed analytically. Based on these equations, the sensitivity of the vacuum gauge and its influencing parameters was investigated and discussed. For comparable conditions, the constant temperature operation shows a significantly higher sensitivity for high pressures, while the constant current operation shows higher sensitivity at low pressures. The sensitivity in both the constant current and the constant temperature mode depends on the ratio of the filament surface area and the parasitic thermal conductance. In addition, for the constant current operation, the sensitivity also depends on the current value and the temperature coefficient of the filament resistor. For the constant temperature operation, the sensitivity additionally depends on the distance of the filament and the reference plane. However, to extend the measurement range of a thermal conductivity vacuum gauge toward low pressures, a reduction of the parasitic thermal conductance is mandatory for both the constant current and the constant temperature mode. Y1 - 2022 U6 - https://doi.org/10.1116/6.0001964 VL - 40 IS - 5 PB - AIP Publishing ER - TY - CHAP A1 - Dams, Florian A1 - Prommesberger, Christian A1 - Schreiner, Rupert T1 - Fabrication process of silicon-tip-arrays for field emission applications T2 - 24th International Vacuum Nanoelectronics Conference (IVNC), 2011 : 18 - 22 July 2011, Historische Stadthalle Wuppertal, Germany N2 - A micromachined process to assemble homogeneous and reproducible tip arrays for field emission applications is developed and characterized. As substrate material p- as well as n-doped silicon is used. Lateral position of the tips is defined by structuring silicon dioxide to discs in a photolithographic process. Vertical structure of the tips is defined by a combination of RIE dry etching with controlled anisotropy and thermally oxidization of silicon in order to sharpen the tips. Hence field emitter arrays (FEAs) can be assembled both as bare and coated cathodes. To assemble field emission diodes, this fabrication process allows placing a metal anode in a micrometer order distance to the tips by a self-aligning procedure. The anode is placed in an evaporation process whereupon sharpening oxide is used as isolator between anode and cathode. Electrical characterization of the cathodes showed very good homogeneity, well alignment and stability over time of emission current from all tips (i.e. 100% efficiency). KW - elemental semiconductors KW - etching KW - fabrication KW - field emission KW - field emitter arrays KW - homogeneity KW - micromachining KW - oxidation, silicon KW - silicon technology Y1 - 2011 UR - https://ieeexplore.ieee.org/document/6004556?arnumber=6004556 SN - 978-3-00-035081-8 SN - 978-1-4577-1243-2 SN - 2380-6311 SN - 2164-2370 SP - 49 EP - 50 PB - IEEE ER -