bluuebunny/crossref_metadata_2025_split huggingface dataset:
Light Emitting Polymermaterials: the Working Base for Flexible Full Color Displays
Authors: Becker Heinrich , Breuning Esther , Büsing Arne , Falcou Aurelie , Heun Susanne , Parham Amir , Spreitzer Hubert , Steiger Jürgen , Stösse Philipp 
Published: June 2019

AbstractIn the last few years, industrial research into materials fulfilling the needs of the maturing OLED display industry has intensified considerably. A first generation of polymers (phenyl- PPVs) is now being commercially exploited in first monochrome polymer LED display applications. Based on these materials, non-planar displays have already been demonstrated. However, those proof of concept devices have been monochrome. Especially the RGB materials need considerable improvement to be suitable for flexible full color displays.We will therefore report on the progress in the development of polymers for red, green, and blue emission. Our main focus here is on improving the properties of various polymers derived from the spiro-bifluorene core.Depending on the color, the main issues vary strongly: For BLUE polymers, efficiency, color coordinates, and processibility are already at a commercial level while operational lifetime still needs strong improvement. RED materials are in an almost contrary situation: here, the operational lifetime is excellent, whereas the efficiency and the driving current are requiring further improvement. For GREEN, achieving saturated emission, whilst maintaining the other properties (high efficiency, long operational lifetime), is still challenging. We will demonstrate the current status of material development within Covion.In addition, we achieved advances in full-color patterning, especially techniques based on Ink-Jet printing. This technology potentially allows the efficient manufacturing of high resolution RGB devices on a variety of substrates, including flexible layers.
Super-elastic Gold Conductors on Elastomeric Substrates
Authors: Chambers Catriona , Lacour Stéphanie P. , Wagner Sigurd , Suo Zhigang , Huang Zhenyu 
Published: June 2019

Abstract3-D displays, sensor skins, mechatronic structures, and e-textiles will rely on deformable and stretchable electronic circuits. It is likely that such circuits will be made of rigid semiconductor islands interconnected with one-time deformable or even elastic metallization. However, free-standing metal films fracture at tensile strains in the order of one percent, well short of the approximately ten-percent extension needed for deformable circuits. We have discovered that flat metal lines made on an elastomeric substrate can be stretched reversibly by ten percent without losing electrical conduction. While this phenomenon of “super-elastic” conductive films is as of yet unexplained, it appears to originate in the diversion of mechanical strain around cracks in the film and through the elastomer substrate. We fabricated 1mm thick poly-dimethylsiloxane (PDMS) membranes with up to 50-nm thick, 1-mm wide gold lines deposited by electron beam evaporation. Then we evaluated the structure of the gold films by optical and scanning electron microscopy, and measured the electro-mechanical characteristics in a strain tester, with contact electrodes applied to the film. We find that 50 nm thick lines retain their electrical conduction up to 30 percent strain. Also, when the tensile strain is cycled between 0 and 10 percent, the electrical resistance in the stressed and relaxed states are reproducible. We will describe substrate and conductor preparation, and their structural and electro-mechanical properties.
Island Edge Coverage By Metal Interconnects for Three Dimensional Circuits
Authors: Bhattacharya Rabin , Wagner Sigurd 
Published: June 2019

AbstractThree-dimensional integrated circuits is a new and exciting field that has been spurred on by the need for conformal displays and detector arrays. These circuits are fabricated by interconnecting rigid sub-circuit islands made on a flat, deformable substrate. To prepare for interconnects, we apply a patterned deformable sacrificial material over the flat substrate. We then deform the substrate, with the sub-circuit islands and the sacrificial pattern on it, to a spherical surface. Following deformation, we evaporate interconnect metal and then liftoff the sacrificial material, leaving only the metal lines that interconnect the islands. The maximum size for a circuit island to remain intact is proportional to the island's thickness. The larger the island has to be, the thicker it must be made to prevent it from cracking. For 50 μm thick Kapton E substrates, it was found that 40 μm square SiNx islandsmust be at least 0.5 μm thick.With such thick islands, sidewall coverage during evaporation of the interconnect metal becomes difficult because of the dome shape of the substrate. Moreover, during substrate deformation, there is delamination that occurs at the island-substrate interface. This delamination forms a gap between the edge of the island, and the substrate. Thick metalization that covers both sidewall and islandsubstrate gap, produces a yield of 97% for 10 micrometer wide aluminum lines.
Ultra-Low Temperature Poly-Si Thin Film by Excimer Laser Recrystallization For Flexible Substrates
Authors: Han Sang-Myeon , Lee Min-Cheol , Kang Su-Hyuk , Shin Moon-Young , Han Min-Koo 
Published: June 2019

AbstractAn ultra-low temperature (< 200°C) polycrystalline silicon (poly-Si) film is fabricated for the plastic substrate application using inductively coupled plasma chemical vapor deposition (ICP-CVD) and excimer laser annealing. The precursor active layer is deposited using the SiH4/He mixture at 150°C (substrate). The deposited silicon film consists of crystalline component as well as hydrogenated amorphous component. The hydrogen content in the precursor layer is less than 5 at%. The grain size of the precursor active silicon film is about 200nm and it is increased up to 500nm after excimer laser irradiation.
High Performance Polysilicon Thin Film Transistor Circuits On Flexible Stainless Steel Foils
Authors: Afentakis Themis , Hatalis Miltiadis K. , Voutsas Apostolos T. , Hartzell John W. 
Published: June 2019

AbstractIn recent years, there has been an increased interest in the use of flexible substrates in microelectronic fabrication. Flexible substrates, such as polymers and metals have the potential to be utilized in roll-to-roll processing, resulting in low cost, rugged systems. Thin flexible stainless steel foils offer a number of advantages over polymers for device and circuit fabrication, most significantly in the increased thermal budget tolerance that they provide. This enables the utilization of high temperature processes in the fabrication and the production of high performance devices and circuits.Thin film transistors have been fabricated on thin stainless steel foils using a variety of crystallization and gate dielectric approaches. N-channel devices with average effective mobility values of 250cm2/Vs and p-channel devices with effective mobility values in the region of 90cm2/Vs were successfully fabricated. Both digital and analog circuits, such as operational amplifiers, ring oscillators and a variety of shift register designs were also fabricated, and their basic performance characteristics will be presented in this paper. The characteristics of ring oscillators having 19 inverter stages operating with speeds of 15MHz or higher, along with the characteristics of various shift register architectures with maximum operating frequencies above 1MHz, will be reported. The impact of process and design parameters on their operation was evaluated and will be addressed in this paper.The results that are presented in this paper constitute the first successful implementation of high performance circuitry having a high degree of scalability and complexity on thin metal foils, thus making the fabrication of efficient, inexpensive and versatile systems on flexible foils for a large variety of applications a realistic prospect.
All-organic field effect transistors
Authors: Parashkov R. , Becker E. , Ginev G. , Schneider D. , Metzdorf D. , Dobbertin T. , Johannes H-H. , Kowalsky W. 
Published: June 2019

AbstractIn this work we present fully patterned organic transistors based on selective electropolymerization of conducting polymers that enables simple fabrication of micron scale features. It involves fabrication of pentacene field effect transistors in which the conducting, insulating parts as well as the substrate are all made of polymers. We have fabricated drain and source electrodes by electropolymerization of 3,4- ethylenedioxythiophene and gate by spin coating of commercially available poly( 3,4- ethylenedioxythiophene) (PEDOT:PSS) aqueous dispersion, polyvinylalcohol for the gate dielectric layer, and pentacene for the organic active layer. We have built a top-gate structure with gate dielectric layer and gate placed on the top of the pentacene layer, and in a such way obtained protection of the active layer could permit enhancement of the operating time of devices. Carrier mobility as large as 0,01 cm2/V s was measured. Functional all- organic transistors have been realised using a simple and potentially inexpensive technology.
Organic Light Emitting Diodes and Photo Detectors Fabricated on a Polymeric Substrate for Flexible Optical Integrated Devices
Authors: Ohmori Yutaka , Kajii Hirotake , Taneda Takayuki , Kaneko Masamitsu 
Published: June 2019

AbstractDirect fabrication of organic light emitting diodes (OLED) on a polymeric substrate, i.e., polymeric waveguide substrate to form a flexile optical integrated devices has been realized. The OELD was fabricated by organic molecular beam deposition (OMBD) technique on a polymeric substrate and a glass substrate, for comparison. The device fabricated on a polymeric substrate shows similar device characteristics to that on a glass substrate. Optical signal of faster than 100 MHz has been created by applying pulsed voltage directly to the OLED with emissive layers utilizing rubrene or porphine doped in 8-hydoxyquinolinum aluminum derivatives. Optical signal transmission with OLED fabricated on a polymeric waveguide with optical connectors has been successfully realized. Optical photo detectors (OPD) utilizing phthalocyanine derivatives with superlattice structure provide increased pulse response with input optical signals, and the OPD with 5 MHz of cut-off frequency has been realized with superlattice structure under reverse bias voltage to the OPD.
Effective Jet Printing of Organic Semiconducting Polymers
Authors: Paul Kateri E. , Wong William S. , Ready Steven E. 
Published: June 2019

AbstractOrganic semiconducting polymers are an attractive alternative to conventional inorganic materials because of the ability to process the polymers from solution and apply them to flexible substrates using lower temperatures and at a lower cost. Direct writing of these materials has the potential to reduce processing steps and material waste. While printing of semiconductors for organic light emitting diodes (OLEDs) is well known, little has been reported on printing semiconductors for organic thin-film transistors (OTFTs). We have developed a process to fabricate TFTs and arrays using jet printing to eliminate all photolithographic patterning. Active layers of the polymeric semiconductor are jet-printed for the active layer. Many factors are found to affect the characteristics of devices having a jet-printed semiconductor layer, including the substrate temperature, surface energy, device geometry, and drop size and overlap. We will discuss the printing conditions that lead to performance similar to that of devices fabricated by spin coating.
Thermal Vibration in nAgI-3Ag2O-2V2O5 Glasses
Authors: Thazin A. , Fujishima Y. , Arai M. , Sakuma T. , Takahashi H. 
Published: June 2019

AbstractThe X-ray diffraction measurement for superionic conducting glasses nAgI-3Ag2O-2V2O5 (n = 2, 5, 10) has been performed at 12, 100, 200 and 290 K. The temperature dependence of structure factor S(Q) of nAgI-3Ag2O-2V2O5 has been discussed based on the theoretical treatment including the thermal vibration of atoms in noncrystalline materials. The effective overall Debye-Waller temperature parameter B increases with the increase of temperature and also with AgI concentration.
Low Temperature PECVD Silicon Oxide For Devices And Circuits On Flexible Substrates
Authors: Meitine Mark , Sazonov Andrei 
Published: June 2019

AbstractThe aim of this research is to develop low temperature gate dielectric/passivation layer for μc-Si and poly-Si based devices and circuits compatible with plastic substrates.The PECVD silicon oxide films were fabricated from mixture of silane and nitrous oxide at 250 °C, 120 °C and 75 °C. Helium, argon and nitrogen were used as diluent gases to optimize density, stress, uniformity, and electronic properties.Chemical composition and bonding in the films were studied by FTIR spectroscopy. The absorption peak at 1075-1080 cm-1 observed in the spectrum of each film corresponds to SiO2 stretching mode. No presence of SiH stretching or NH-stretching vibrations was found in the FTIR spectra of the samples.Film uniformity was varied from 1.44 % to 5.60 % for 3“×3” area. Four wafers were processed at the same time. The deposited films have compressive stress varied from 0.063 GPa to 0.117 GPa. Respective film density is in the range from 1.63 g/cm3 to 1.77 g/cm3.The electronic properties were studied on MOS capacitors with 200 nm thick SiOx. The dielectric permittivity was in the range between 2.03 and 3.57. The dielectric breakdown at 9 MV/cm was observed for the films deposited at 120 °C. The films deposited at higher temperatures are characterized by lower leakage current density, which was 3.7.10-10 A/cm2 for the sample deposited at 250 °C, 9.10-9 A/cm2 for 120 °C, and 2.2.10-8 A/cm2 for 75 °C at 5 MV/cm.The a-Si:H based TFTs were fabricated using low temperature oxide as gate dielectric. TFTs demonstrate threshold voltage (3.02 – 4.12 V) and mobility (0.12 – 0.59 cm2/Vs) comparing with those using silicon nitride.
Nanotectonics: Direct Fabrication of All-Inorganic Logic Elements and Micro-Electro-Mechanical Systems from Nanoparticle Precursors
Authors: Wilhelm Eric J. , Jacobson Joseph 
Published: June 2019

AbstractThe reduced melting point and high solubility of inorganic nanoparticles have been shown to be useful in the low-temperature solution-based fabrication of semiconductor devices. These inks have been patterned using various techniques to form inorganic logic elements, multi-layer structures, and MEMS. Here we report a new technique known as offset liquid embossing that is used to print the nanoparticle inks. Structures created include multiple layers of gold and spin-on-glass printed without the need for etching or planarization, and 100 nm resolution.
High-quality inkjet-printed multilevel interconnects and inductive components on plastic for ultra-low-cost RFID applications
Authors: Molesa Steven , Redinger David R. , Huang Daniel C. , Subramanian Vivek 
Published: June 2019

AbstractIn recent years, there has been tremendous interest in all-printed electronics as a means of achieving ultra-low-cost electronic circuits with uses in displays and disposable electronics applications such as RFID tags. While there have been a few demonstrations of printed organic transistors to date, there has been little work on the associated passive component and interconnection technologies required to enable the development of all-printed RFID circuits. In particular, low-resistance conductors are crucial to achieve the high-Q inductors necessary for RFID. Here, we demonstrate inkjetted nanoparticle-Au conductors on plastic with sheet resistances as low as 0.03 ohms/square. We describe the optimization of the jetting parameters, and their impact on final film morphology and electrical properties. We also demonstrate a bridging technology based on an inkjetted polyimide interlevel dielectric. Using this process, we demonstrate multilevel interconnect and passive component structures including conductor patterns, crossover bridges, and tapped planar spiral inductors. Together, these represent an important step towards the realization of all-printed RFID.
A Basic Concept of Novel Hybrid Opto-Elctronic Integrated Systems with Textile Structures
Authors: Tanaka Kuniaki 
Published: June 2019

AbstractAccording to the situation recognition of a basic limit of electronics expansion in silicon planar technology, one proposal based on a new technology completely different from planar structure is done here. The new concept of the technology is “textile structure” for integrated optoelectronic circuit. The background of the new concept is shown from some historical view point. The concept is also discussed as an opto-electronic united circuit and a “Clothes” level system from application-view point. Characteristics and elemental technology of the textile hybrid system are considered for future development of this concept. Several concrete compositions and characteristics of the proposed system are compared with those of present technology to construct a new electronics system. This proposal is also discussed in flexible electronics concept.
An Inverter Woven from Flat Component Fibers for e-Textile Applications
Authors: Bonderover Eitan , Wagner Sigurd , Suo Zhigang 
Published: June 2019

AbstractIn the most fundamental approach, e-Textile circuits will be made by weaving component fibers into circuits. The weaving pattern will determine the circuit function. A key requirement of such e-Textile circuits is reliable electrical contact between fibers. Contacts which rely only on the pressure between fibers are preferred since they preserve the drapability of real fabrics. Since thin-film device fabrication technology is planar, the component fibers, made by the slit-film technique, are flat. Thus a slight edge-to-edge curvature (with a radius of curvature as large as 500mm) can either prevent or promote electrical contact. Using fibers with thin-film transistors of amorphous silicon, we study the processes that produce the desired fiber curvature. A layer of stressed silicon nitride is used to create the curvature. The stress in this layer can be controlled by the deposition parameters. We present successful fabrication of curved fibers with vastly improved electrical contact. We also present electrical characterization of woven transistor circuits
Gallium zinc oxide coated polymeric substrates for optoelectronic applications
Authors: Fortunato E. , Gonçalves A. , Marques A. , Assunção V. , Ferreira I. , Águas H. , Pereira L. , Martins R. 
Published: June 2019

AbstractHighly transparent and conductive ZnO:Ga thin films were produced by rf magnetron sputtering at room temperature on polyethylene naphthalate substrates. The films present a good electrical and optical stability, surface uniformity and a very good adhesion to the polymeric substrates. The lowest resistivity obtained was 5×10-4 Ωcm with a sheet resistance of 15 Ω/sqr and an average optical transmittance in the visible part of the spectra of 80 %. It was also shown that by passivating the polymeric surface with a thin SiO2 layer, the electrical and structural properties of the films are improved nearly by a factor of 2.
Silicon Nanocrystal Nucleation as a Function of the Annealing Temperature in SiOx Films
Authors: Daldosso N. , Das G. , Dalba G. , Larcheri S. , Grisenti R. , Mariotto G. , Pavesi L. , Rocca F. , Priolo F. , Franzò G. , Irrera A. , Miritello M. , Pacifici D. , Iacona F. 
Published: June 2019

AbstractSi nanocrystals (Si-nc) embedded in amorphous silica matrix have been obtained by thermal annealing of substoichiometric SiOx films, deposited by PECVD (plasma enhanced chemical vapour deposition) technique with different amount of Si concentrations (42 and 46 at.%). Both nucleation and evolution of Si-nc together with the changes of the amorphous matrix have been studied as a function of the annealing temperature. The comparison of x-ray absorption measurements in Total Electron Yield (TEY) mode at the Si k-edge with photoluminescence (PL), FTIR and Raman spectra, allowed clarifying the processes of Si-nc formation and structural evolution as a function of the annealing temperature and Si content.
Exceptionally High Radiative Efficiencies in Silicon
Authors: Green M.A. , Wang A. , Zhao J. , Trupke T. , Cho E-C. , Xia J. 
Published: June 2019

AbstractAlthough silicon is known as a poor emitter of light, recent work has demonstrated silicon light emission efficiencies in the range normally associated with III-V semiconductors. The present paper explores the light emission efficiency potential of silicon as well as the scope for implementing silicon optical functions into high density integrated circuits.
Erbium-silicon-oxide Nano-complexes Prepared by Wet Chemical Synthesis
Authors: Isshiki H. , Dood M.J.A. de , Kimura T. , Polman A. 
Published: June 2019

AbstractAn entirely new method to fabricate optically active and carrier-mediated excitable erbium complexes on silicon is presented. The Er-Si-O nano-complexes are formed by spin-coating a Si (100) substrate with an ErC13 solution, followed by a rapid thermal oxidation and annealing sequence (RTOA). Intense room-temperature luminescence is observed from the Er-Si-O nano-complexes, with a line width as narrow as 4 meV at room temperature. The Er emission at 1.53 μm can be excited both directly and through photo carriers. Formation and optical activation of the Er-Si-O nano-complexes are discussed. In addition, an application of the wet chemical synthesis technique to incorporation of the Er-Si-O nano-complexes into nano-porous silicon waveguides is demonstrated.
Formation and Electric Properties of Disordered Yb Layers on Si(111)7×7 Surface
Authors: Galkin Nickolay G. , Goroshko Dmitrii L. , Gouralnik Alexander S. , Dotsenko Sergei A. , Boulatov Andrei N. 
Published: June 2019

AbstractInterface formation in Yb/Si(111) system has been investigated by AES and EELS spectroscopy and in situ Hall measurements at room temperature. It was found that interface formation process may be divided into five stages: 1) two-dimensional growth of Yb, 2) intermixing and formation of two-dimensional Yb silicide, 3) formation of 3D silicide islands, 4) growth of Yb on 3D silicide islands, 5) coalescence of 3D Yb – Yb silicide islands and formation of continuos Yb film. We attribute the observed character of conductivity in Yb/Si(111) system to the evolution of morphological and electrical properties of the growing Yb layer (2D Yb, silicide, metal) rather than to the changes within the space charge layer under the surface. Some amplitude oscillations have been observed in sheet conductivity, hole mobility and surface hole concentration within the coverage range below 6 ML where formation of a continuos Yb silicide film completes. Conductivity oscillations are explained by transition from semiconductor-type conductivity at the first growth stages (two-dimensional Yb growth) to metal-like conductivity of 2D and 3D Yb silicide films.
Integrated Silicon Infrared Microspectrometers
Authors: Kong S.-H. , Graaf G. de , Wolffenbuttel R.F. 
Published: June 2019

AbstractDesign, fabrication and performance of a microspectrometer for operation in the infrared spectral range between 1 and 8 μm and fabricated in silicon are presented. The opto-electrical system is composed of two bonded silicon wafers, which have been subjected to microelectronic process compatible micromachining to enable co-integration of the optical components (an aluminum based grating, an optical path in crystalline silicon and an array of integrated polysilicon thermocouples) with readout circuits in silicon. The FWHM is smaller than 0.5 μm at λ= 5 μm. The performance is compared to alternatives and directions for improving the selectivity are given.