By Topic

Electronics Technology (ISSE), 2010 33rd International Spring Seminar on

Date 12-16 May 2010

Filter Results

Displaying Results 1 - 25 of 117
  • Polymer electronics towards system integration

    Publication Year: 2010 , Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (875 KB) |  | HTML iconHTML  

    Polymer electronics, or Polytronics, as the short name, is a promising technology for low-cost and large-area electronic systems, based on novel organic materials with conducting and semiconducting properties, not addressable by conventional silicon technology. The new properties of this plastic materials are a combination of the electronic and optical properties of metals and semiconductors and the properties of polymers and small molecules. Using active and passive electronic and photonic components, based on organic materials, allows system integration for a specific application. These systems can be made on flexible foil substrates, allowing the processing of large area electronics. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Noise characteristics of cold emission cathodes

    Publication Year: 2010 , Page(s): 7 - 9
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (297 KB) |  | HTML iconHTML  

    The paper presents the noise characteristics of microscopic cathode based on Schottky field emission. Schottky emission is considered to be the predominant electron source technology in actual focused electron beam equipment. For the ideal electron source, it is necessary to achieve following properties: small source size, low electron emission energy spread, angular intensity (an emission current per unit solid angle), low noise, long-term stability and a simple and low-cost operation. The noise spectroscopy in time and frequency domain is based on measuring cathode's voltage noise density in ultra-high vacuum conditions (UHV) in order to avoid environment interaction with ions which are present in the vacuum chamber. The first part of the article describes basic concept of electronic noise together with the description of used cathodes. Second part focuses on the method of measurement and in the last part, reached results are presented together with suitable explanation according to the concept of electronic noise. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Thermomechanical analysis of a bulk of electrically conductive adhesive

    Publication Year: 2010 , Page(s): 10 - 13
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (704 KB) |  | HTML iconHTML  

    Mechanical properties of isotropically conductive adhesives depend not just on the internal structure and composition (amount and type of binder and filler) of the adhesive, but also on chemical processes that are influenced by curing. Thermomechanical analysis allows to distinguish the point when the adhesive is fully cured, it may reveal a difference in mechanical properties after different modifications of the adhesive, it may give a clue to better thermal processing of the adhesive while curing. Thermal analysis of totally nine types of adhesive modifications was performed, particularly the influence of carbon nanotubes addition, silver nanoparticles and colloidal silver was observed. In our tests, both one-component and two-component adhesives were used. The overview of tested adhesives and their modifications is described in table 1. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Phthalocyanine layers for humidity detection

    Publication Year: 2010 , Page(s): 14 - 17
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (270 KB) |  | HTML iconHTML  

    This article deals with the research of different types of phthalocyanines for humidity detection. Thin layers of various phthalocyanines are exposed to water vapors and then electrical properties of these layers are measured. Potentially suitable materials are deposited on the substrates with interdigital electrodes and subsequently impedance-humidity characteristics are measured. Comparison of these materials, their features and responses to an ambient humidity are discussed in more detail. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Metallographic preparation of the SnAgCu solders for optical microscopy and EBSD Investigations

    Publication Year: 2010 , Page(s): 18 - 23
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1231 KB) |  | HTML iconHTML  

    In order to investigate the microstructure of lead-free SnAgCu solders by optical microscopy and Electron Backscatter Diffraction it is necessary to provide a qualitative metallographic preparation. The difficulties of a preparation of these solders are connected with a high softness and presence of hard intermetallic compounds. They are discussed in this study and the appropriate recipe is proposed. The samples were manufactured of SnAg3Cu0.7 (wt. %) solder in a form of solder spheres with a diameter of 270 μm, cooled at the rate of 1.1 K/s. The metallographic preparation was carried out on a TegraSystem from Struers. The quality of the prepared samples was checked by image Orientation Imaging Microscopy softwarequality maps, created by the Orientation Imaging Microscopy software. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Characterization of the organic field-effect transistor based on solution processed P3HT

    Publication Year: 2010 , Page(s): 24 - 29
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (251 KB) |  | HTML iconHTML  

    The purpose of this paper is to present results of measurements taken on organic field effect transistors based on P3HT solution processed organic semiconductor. All discussed samples have been prepared both under ambient atmospheric conditions and in the dry nitrogen environment on rigid Si substrates covered with thermally grown SiO2 The electrical behaviour of OFETs has been subsequently examined under different test conditions. In particular, the overall device performance in normal room atmosphere as well as in the vacuum has been of special interest. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Humidity influence on antistatic properties of optical coatings

    Publication Year: 2010 , Page(s): 30 - 34
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (219 KB) |  | HTML iconHTML  

    In this work antistatic properties as ability to dissipate static electricity of different types of materials were investigated. Dissipation of static charge was investigated in relation to humidity changes. It has been shown, that decreasing humidity affected badly on charge decay time of some optical lenses examples. Additionally single layer of TiO2 thin films on SiO2 substrates were measured in the same experimental conditions and collected results were compared with those for optical lenses in relation to their antistatic properties. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Influence of neodymium dopant on TiO2 structure

    Publication Year: 2010 , Page(s): 35 - 39
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (688 KB) |  | HTML iconHTML  

    In this work structural properties of TiO2 thin films doped with different amounts of Nd have been presented. Thin films were deposited on silicon substrates using high energy reactive magnetron sputtering process and for the measurements TiO2 doped with 0.84 at. % and 8.51 at. % of Nd have been selected. Diversification of the thin film surface was investigated using atomic force microscope. The results have shown that distribution of grains size the thin films was dependent on the amount of neodymium dopant. Moreover structural characterization of the thin films with use of X-Ray Diffraction method has shown that different structure of the TiO2 thin films was received with selected amount of Nd (0.84 and 8.51 at. %) and by additional annealing. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Stabilization of organic materials for sensors

    Publication Year: 2010 , Page(s): 40 - 44
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (317 KB) |  | HTML iconHTML  

    This paper deals with research and development of organic humidity sensors. These sensors are based on organic sensitive layer which is applied on the substrate with interdigital electrodes. The main work is focused on the stabilization of organic sensor layers. The stabilisation of mechanical and electrical parameters is based on passive polymer matrix where the active organic sensitive material is fixed. The sensor sensitivity, impedance-humidity characteristics and long term stability of electrical parameters were measured and discussed in detail. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Control unit for smart concrete used as resistive heating

    Publication Year: 2010 , Page(s): 45 - 49
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (438 KB) |  | HTML iconHTML  

    This paper deals with conductive concrete materials and its testing and controlling. Multipurpose remotely-controlled thermostat, called iTHERMST, was designed and built to test and evaluate new samples of the cement-based material with high specific heat and high thermal conductivity. iTHERMST tests and collects various data that can be imported directly to PC software for further evaluations. New possible controlling algorithms were introduced, described and finally tested in practice. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Influence of metallographic preparation on electron backscatter diffraction characterization of copper wire bonds

    Publication Year: 2010 , Page(s): 50 - 54
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (563 KB) |  | HTML iconHTML  

    The advantages of copper wire bonding compared to gold wire bonding, such as lower material costs, have led to an increased interest in reliability of copper bonds. The knowledge of the bonded wire microstructure is essential to achieve high-reliability bonding. This study focuses on the metallographic preparation of a bonded cross-sectioned sample for achieving a high-quality planar surface, suitable for electron backscattered diffraction (EBSD) technique. This technique was used for crystal orientation mapping of a thermosonic (ball) bonded copper wire. Because of the sensitivity of EBSD technique to surface defects and preparation artifacts, it was used for the evaluation of preparation quality. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Enhanced hole transport in multilayer organic based devices

    Publication Year: 2010 , Page(s): 55 - 60
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2355 KB) |  | HTML iconHTML  

    Multilayer Organic Based Devices (OBDs) were constructed by subsequent casting of organic films (from polymers, soluble in the same organic solvent). The problem with dissolution of the underlying layer was avoided by using electrophoretic deposition technique. Optimized conditions for electrophoretic deposition (EPD) of thin films with homogeneous and smooth surfaces, as confirmed by SEM, were found. The EPD deposition, carried out at constant current, requires continuous increase of the voltage between the electrodes. In this way the decreased deposition rate caused by the decreased concentration of the material in the suspension and the increased thickness of the film deposited is compensated. The SEM images and the current voltage characteristics recorded, show that the hole transport polyvinylcarbazole (PVK) underlayer survive the treatment with the suspension used for the electrophoretic deposition of the active poly[2-methoxy-5-(3,7-dimethyloctyloxy)-1,4-phenylene vinylene] electroluminescent layer. The introduced PVK hole transport layer increases the device current, as confirmed by the current-voltage measurements. The results obtained demonstrate the possibility of OBDs preparation for electroluminescent and photovoltaic application. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Authors index

    Publication Year: 2010 , Page(s): 1 - 3
    Save to Project icon | Request Permissions | PDF file iconPDF (84 KB)  
    Freely Available from IEEE
  • The interface between different types of thick film layers

    Publication Year: 2010 , Page(s): 61 - 64
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (183 KB) |  | HTML iconHTML  

    The investigation of conductive and resistive layers interface is topic of the work. Layers of measured structure were deposited by screen-printing of polymer pastes. The measured structure consists of contact area with different geometry. Contact resistance of interface between conductive and resistive layers was measured as a parameter of quality. The three-wire method was used for measurement. Experimental results were analyzed in the context of contacts geometry and frequency of powered signal. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Characterization of reactive sputtered ITO and TiO2/ITO thin films for applications at elevated temperatures

    Publication Year: 2010 , Page(s): 65 - 70
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (738 KB) |  | HTML iconHTML  

    In this work are discussed the technology for preparing and characterisation of indium-tin oxide (ITO) and ITO with titanium oxide underlayer thin films with properties appropriate for usage at elevated temperatures as heat reflective coatings and gas sensors. For preparing the samples the methods of radio frequency (RF) and DC-magnetron reactive sputtering were used. Sputtering of indium-tin and ITO targets with different composition in presence of oxygen as reactive gas was made. The technological parameters were studied to obtain films with optimal properties at different substrates - glass, silicon, quartz. Heating of the substrates during the preparation and their postdeposition annealing in different environments also were studied. Comparison how the different techniques and target composition affect on the films' properties was made. The composition and microstructure of the films were studied by XPS, EPMA and XRD, the surface of the films was observed by a high-resolution SEM. Thorough profile analyses on the structure changes were performed applying XPS. Some unwished phenomena like diffusion and interactions with the substrate also were investigated. To identify the optical properties of the films the methods of visual spectrophotometry and laser ellipsometry were used. The reflectance of the films in the thermal IR range was investigated by FTIR spectrophotometer. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Piezoelectric thick films on LTCC substrates

    Publication Year: 2010 , Page(s): 71 - 76
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (348 KB) |  | HTML iconHTML  

    Piezoelectric thick films based on Pb(Zr, Ti)O3 (PZT) were prepared on LTCC substrates and on relatively inert alumina substrates. The results obtained with the alumina were used as a reference. The microstructures of the cross-sections of the PZT layers were investigated using scanning electron microscopy (SEM) and energy-dispersive X-ray (EDS) analysis. The dielectric permittivities, dielectric losses, remanent polarisations, coercitive fields and piezoelectric constants d33 were measured. The dielectric and piezo electric characteristics of the PZT fired on the LTCC substrate deteriorated, as compared with samples on alumina, due to interactions between the LTCC substrate and the PZT layers. This was attributed to the diffusion of the glassy phase from the LTCC into the active PZT layer and to the diffusion of the PbO from PZT layer into the LTCC substrates. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Fabrication of miniaturized thick-film arms for thermoelectric microgenerators

    Publication Year: 2010 , Page(s): 77 - 81
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (713 KB) |  | HTML iconHTML  

    In the paper fabrication process of miniaturized thick-film arms for metal-based thermoelectric microgenerator is presented. Ones arms were fabricated using special photoimaginable ink and photolithography processing. Second arms were screen-printed using standard ink, then laser shaped. In the result process of fabrication narrow paths for microgenerator was elaborated. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Miniaturization of thick–film resistors by laser–shaping

    Publication Year: 2010 , Page(s): 82 - 86
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (745 KB) |  | HTML iconHTML  

    This paper presents manufacturing process of laser-shaped thick-film resistors as well as their chosen electrical, geometrical, microstructural and stability properties. Test structures were based on commercially available conductive and resistive pastes deposited on Al2O3 substrates. Resistors made in standard screen printing process after firing were patterned using laser beam in order to minimize their planar dimensions to tenths of millimeter and below. Prepared samples were subjected to number of electrical tests and some characteristic parameters like temperature coefficient of resistance (TCR) were calculated based on these measurements. Test samples were also exposed to long-term thermal ageing. Moreover the laser profilometer was used for three-dimensional characterization of components. Scanning electron microscope (SEM) was used for the microstructural analysis and the EDS (Energy Dispersive X-ray Spectroscopy) of samples is given. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Lead-oxide-free copper thick-film paste for alumina substrates

    Publication Year: 2010 , Page(s): 87 - 92
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1095 KB) |  | HTML iconHTML  

    The present paper relates to a lead-oxide-free copper thick-film paste for printing on ceramic substrates, especially on alumina. Commercialized copper thick-film pastes usually consist of copper powder with lead-oxide glass, which should be avoided in regard to the RoHS Certificate of Conformity. The screen printing technology could be an alternative method instead of the standard DCB process, particularly for structured and thinner films. In this case it is meaningful to use thick-film pastes to form such structures. In the first steps of the paste development process the rheological properties could successfully realized. That means a paste with high solid content and good structured conductor lines was established. Furthermore the adherence of the copper thick-film on alumina substrates could be highly improved by adding additives. Also the solder ability was achieved to 95% by adding another additive, which acts as a wetting agent. FESEM and EDX characterizations show the mechanical adhesion process, which belongs to the formation of a ceramic-metal-interlayer, where copper aluminate is build. Moreover cross section images of the examined copper thick-film layers show a sinter body with pores in the copper film, which have to be minimized, to improve the electrical and mechanical properties. In summary can be said, that previous investigations showed measured values, which nearly achieve the aim values and a lead-oxide-free copper thick-film paste is developed, which can be tested for DCB-applications. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Permittivity and conductivity of various LTCC–tapes at high temperature

    Publication Year: 2010 , Page(s): 93 - 98
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (435 KB) |  | HTML iconHTML  

    Various LTCC-tape materials have been characterized regarding their RF-properties at elevated temperature by means of impedance measurement of square-shaped capacitor samples up to a frequency of 3 MHz. Parameters of an equivalent circuit were fitted to reconstruct the impedance characteristics and the parameters extracted. The activation energies of samples were derived from the impedance model. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • PTC temperature sensors on curved LTCC–layers

    Publication Year: 2010 , Page(s): 99 - 102
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (627 KB) |  | HTML iconHTML  

    To carry out studies on the warming-up of wind instruments, temperature sensors are required that exactly fit into the tube of the instrument. A PTC (positive temperature coefficient) temperature sensor was developed in LTCC (low temperature co-fired ceramics) technology, solving this problem. To keep the overall design small, a very simple geometry was used that just consists of one ceramic tape layer with PTC resistor and 4-wire connection pads on top. The PTC sensor was laminated around a rod and sintered inside a pipe to achieve the desired curvature. Various different ceramic tape materials were used and the electrical properties of the PTC sensor were measured with respect to varying curvature (flat, diameter 12 mm and 18 mm) where resistor elements were positioned in both axial and radial orientation. Finally, the results were obtained by usage of CeramTec GC tape, ESL PTC26xx-I PTC-paste and ESL 9695-G conductor paste. The curvature showed no influence on the TCR (resistive temperature coefficient). The resistance of the curved resistors in axial as well as radial orientation was lower compared to the flat structure. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Tolerance design of curing process of electrically conductive adhesives

    Publication Year: 2010 , Page(s): 103 - 106
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (168 KB) |  | HTML iconHTML  

    The work was directed at examination of influence of tolerances of curing process parameters on the tolerances of the resistance and nonlinearity of a current vs. voltage characteristic of adhesive joints. The joints were formed of electrically conductive adhesive with isotropic electrical conductivity of an epoxy type filled with silver flakes. Mathematical models for the resistance and nonlinearity were found using factorial experiments of the type 22. Tolerance design was carried out for these models. It was found that tolerances of the resistance and nonlinearity depend more on the time of curing than on the curing temperature. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Bumping technologies of fine-pitch BGA components

    Publication Year: 2010 , Page(s): 107 - 112
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (555 KB) |  | HTML iconHTML  

    The assembling technology of fine-pitch Ball Grid Arrays (BGAs) is used for high-end applications such as technology of very high density circuits and package-on-package structures. Vapor phase soldering is a perspective technology, but as it is still not very widespread in the industry and in research laboratories, there are a lot of things to examine to standardize the process and to get more experiences. SAC solder bumps made with different technologies were compared to each other and to bumps of commercial BGA components. Another aim was to determine the limits of our laboratory facilities in bumping and PWB technologies. Bumping experiments were carried out on model BGA components with stencil printing, reflowed with vapor phase and with applying solder with mini-wave selective soldering equipment. The optimization of the solder amount and the appropriate technology was in the focus of our research. To have acceptable, high, uniform and good quality bumps, we developed these processes with parameter optimization. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Solderability measurement of copper with different surface finishes

    Publication Year: 2010 , Page(s): 113 - 116
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (229 KB) |  | HTML iconHTML  

    This article deals with solders wettability measurement of materials with different surface finishes, which are commonly used as solder pads on printed circuit board. The measurement was carried out on two type of solders (Sn63Pb37, Sn95,5Ag3,8Cu0,7), two types of fluxes (94-RXZ-M (IPC-ANCI-J-STD-004 - REL0), 323-ITV (C-ANCI-J-STD-004 - REL1)) and as testing material we used one-side plating PCB (FR4) with four types of surface finishes (pasivated copper, H.A.L, immersion tin, chemical gold plating). For the measurement we have used one of the commonly used wettability evaluation methods - wetting balance (meniscograph) method. Wetting balance method measures the wetting force when the test specimen is immersed into the molten solder bath. Wetting force is measured as a function of time and recorded as wetting curve. We marked the wettability, according to the shape of wetting curve, for each testing combination and sorted them into the table. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Package–on–Package – Review on a Promising Packaging Technology

    Publication Year: 2010 , Page(s): 117 - 122
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (948 KB) |  | HTML iconHTML  

    Package-on-Package (PoP) components are BGA packages stacked on each other. With this method not only board space is saved, but signal routes are also shortened. It was presented by a cooperation of Amkor and Nokia. The vertical 3 dimensional stacking of BGA components broadens the possibilities of planar surface mounting technology. The PoP technology is constantly evolving; the latest solutions offer wide variety of bumping and stacking technologies. This paper is a review on this aspiring 3D packaging method. Preliminary soldering experiments with dummy packages are also presented. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.