Thick Film Metallization of AlN by Reactive Binders

The thick-film metallization of AlN has received considerable attention because of its potential applications in electronic packaging. Here we reported on the thick film metallization of AlN by reactive binders. The metallization paste of Ag was prepared with organic vehicle of castor oil, ethyl cellulose and beta-terpineol and reactive binders of TiB2 and Co3O4. The control of the paste viscosity was discussed by changing the dispersant content. Meanwhile effects of the components and sintering process on the thick film properties were investigated. The properties of metallization film were analyzed with XRD, SEM and electrical test. The adhesion strength and the electrical resistance of the film were 12.7MPa and 5.3mΩ/□ respectively when the paste composition of Ag, TiB2, Co3O4 and the organic vehicle was 72.8%, 1.5%, 0.7% and 25% and the film was sintered in air at 850°C for 15 minutes.

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Pressure-Assisted Sintering of Buried Thick Film Resistors in LTCC

Additional Conferences (Device Packaging HiTEC HiTEN & CICMT) ◽

10.4071/cicmt-wp21 ◽

2015 ◽

Vol 2015 (CICMT) ◽

pp. 000239-000244

Author(s):

Andreas Heunisch ◽

Victor de Seauve ◽

Torsten Rabe

Keyword(s):

Thick Film ◽

Electrical Resistance ◽

Particle Distribution ◽

Laser Diffraction ◽

The Other ◽

Sintering Process ◽

Sheet Resistivity ◽

Green Tape ◽

Small Fluctuation ◽

Conductive Phase

In this work, the effect of the pressure-assisted sintering process on buried thick film resistors integrated in LTCC multilayer has been studied. Four commercial resistor pastes with sheet resistivities between 10 kΩ and 10 MΩ/cm were analyzed. First they were characterized by SEM/EDX, XRD and Laser diffraction to determine composition and particle distribution. The pastes consist of isolating particles and of Ruthenium based particles that are supposed to build the conductive phase. The pastes were screen printed on LTCC green tape (DP 951) and buried in four layer laminates. Sintering was done in two ways, pressureless (PLS) and also pressure-assisted (PAS). The pressureless sintered resistors showed electrical resistance values roughly in the range of the nominal sheet resistivity and only relatively small fluctuation within one sample. The PAS samples on the other hand showed significantly higher resistances and larger deviations. The microstructure of the sintered resistors was again investigated by SEM and XRD. It seems that the resistivity is determined by the ratio of the two Ruthenium phases RuO2 and Pb2Ru2O6.5, where RuO2 has the higher conductivity. Buried resistors cannot be trimmed by a laser to adjust the resistance. But we discovered that a refiring step will reduce and normalize the resistivity of the PAS resistors significantly.

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Influence of the organic vehicle and inorganic additives on the properties of thick film pastes for AlN

International Symposium on Microelectronics ◽

10.4071/isom-2013-ta33 ◽

2013 ◽

Vol 2013 (1) ◽

pp. 000078-000083

Author(s):

Richard Schmidt ◽

Marco Wenzel ◽

Kathrin Reinhardt ◽

Uwe Partsch ◽

Lars Rebenklau ◽

...

Keyword(s):

Steady State ◽

Thick Film ◽

Sheet Resistance ◽

Significant Influence ◽

Substrate Material ◽

Film Deposition ◽

Film Properties ◽

Organic Vehicle ◽

Conductive Phase ◽

Dynamic Experiments

New conductor pastes for AlN as substrate material with fired films of a sheet resistance below 25 mOhm/sq were investigated. The pastes consist of AgPd as conductive phase for leach resistance. Other paste ingredients are glasses of matched composition for adhesion and densification properties, little amounts of inorganic additives and organic vehicles for film deposition. The latter has a significant influence on the paste deposition and the resulting film properties as well. In order to shine light into these relationship systematic rheological studies of the organic vehicle and the manufactured pastes were performed. The rheological investigations include measurements in rheological steady-state as well as dynamic experiments. In addition, the solder properties of the fired film were studied. FESEM analyses were performed on the surface of the fired films.

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Synthesis and Characterization of Novel Castor Oil-Based Polyol for Potential Applications in Coatings

JOURNAL OF RENEWABLE MATERIALS ◽

10.32604/jrm.2019.00045 ◽

2019 ◽

Vol 7 (1) ◽

pp. 31-40 ◽

Cited By ~ 1

Author(s):

Azam Sardari ◽

Ali Asghar Sabbagh Alvani ◽

Seyed Reza Ghaffarian

Keyword(s):

Castor Oil ◽

Synthesis And Characterization ◽

Potential Applications

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A method of adhesion strength test for thick film

Microelectronics Reliability ◽

10.1016/0026-2714(94)90431-6 ◽

1994 ◽

Vol 34 (12) ◽

pp. 1973

Keyword(s):

Thick Film ◽

Adhesion Strength ◽

Strength Test

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Environmental tests of embedded thin- and thick-film resistors in comparison to chip resistors

Circuit World ◽

10.1108/cw-10-2013-0039 ◽

2014 ◽

Vol 40 (1) ◽

pp. 7-12 ◽

Cited By ~ 5

Author(s):

Wojciech Steplewski ◽

Andrzej Dziedzic ◽

Janusz Borecki ◽

Grazyna Koziol ◽

Tomasz Serzysko

Keyword(s):

Thin Film ◽

Thick Film ◽

Electrical Resistance ◽

Printed Circuit Boards ◽

Base Material ◽

Forming Process ◽

Content Type ◽

Thin Film Resistors ◽

Embedded Resistors ◽

The Impact

Purpose – The purpose of this paper is to investigate the influence of parameters of embedded resistive elements manufacturing process as well as the influence of environmental factors on their electrical resistance. The investigations were made in comparison to the similar constructions of discrete chip resistors assembled to standard printed circuit boards (PCBs). Design/methodology/approach – The investigations were based on the thin-film resistors made of NiP alloy, thick-film resistors made of carbon or carbon-silver inks as well as chip resistors in 0402 and 0603 packages. The polymer thick-film resistive films were screen-printed on the several types finishing materials of contact terminations such as copper, silver, and gold. To determine the sensitivity of embedded resistors versus standard assembled chip resistors on environmental exposure, the climatic chamber was used. The measurements of resistance were carried out periodically during the tests, and after the exposure cycles. Findings – The results show that the change of electrical resistance of embedded resistors, in dependence of construction and base material, is different and mainly not exceed the range of 3 per cent. The achieved results in reference to thin-film resistors are comparable with results for standard chip resistors. However, the results that were obtained for thick-film resistors with Ag and Ni/Au contacts are similar. It was not found the big differences between resistors with and without conformal coating. Research limitations/implications – The studies show that embedded resistors can be used interchangeably with chip resistors. It allows to save the area on the surface of PCB, occupied by these passive elements, for assembly of active elements (ICs) and thus enable to miniaturization of electronic devices. But embedding of passive elements into PCB requires to tackle the effect of each forming process steps on the operational properties. Originality/value – The technique of passive elements embedding into PCB is generally known; however, there are no detailed reports on the impact of individual process steps and environmental conditions on the stability of their electrical resistance. The studies allow to understand the importance of each factor process and the mechanisms of operational properties changes depending on the used materials.

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Facile Synthesis of Sprayed CNTs Layer-Embedded Stretchable Sensors with Controllable Sensitivity

Polymers ◽

10.3390/polym13020311 ◽

2021 ◽

Vol 13 (2) ◽

pp. 311 ◽

Cited By ~ 1

Author(s):

Hammad R. Khalid ◽

Iqra Choudhry ◽

Daeik Jang ◽

Nadir Abbas ◽

M. Salman Haider ◽

...

Keyword(s):

Electrical Resistance ◽

Electronic Devices ◽

Polymer Layer ◽

Facile Synthesis ◽

Optical Images ◽

Significant Interest ◽

Potential Applications ◽

Facile Fabrication ◽

Stretchable Sensors ◽

Solution Volume

Flexible electronic devices have gained significant interest due to their different potential applications. Herein, we report highly flexible, stretchable, and sensitive sensors made of sprayed CNT layer, sandwiched between two polymer layers. A facile fabrication process was employed in which the CNT solution was directly sprayed onto a patterned bottom polymer layer, above which a second polymer layer was casted to get a sandwiched composite structure. Varying amounts of CNT solution (i.e., 10, 25, 40, 70, and 100 mL) were sprayed to get conductive CNT layers of different thicknesses/densities. The physical characteristics of the conductive CNT layers were studied through SEM and optical images. The starting electrical resistance values (without strain) as well as the changes in electrical resistance against human body motions were monitored. The synthesized samples exhibited good response against finger and wrist bending. The conductivity of the samples increased with increase of CNT solution volume while the sensitivity followed the inverse relation, suggesting that the sensors with controlled sensitivity could be fabricated for targeted strain ranges using the proposed method.

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One-Step Quaternization/Hydroxypropylsulfonation to Improve Paste Stability, Adhesion, and Film Properties of Oxidized Starch

Polymers ◽

10.3390/polym10101110 ◽

2018 ◽

Vol 10 (10) ◽

pp. 1110 ◽

Cited By ~ 13

Author(s):

Wei Li ◽

Zhenzhen Xu ◽

Zongqian Wang ◽

Jian Xing

Keyword(s):

Tensile Strength ◽

Degree Of Crystallinity ◽

Trimethylammonium Chloride ◽

Film Properties ◽

Moisture Regain ◽

Breaking Elongation ◽

End Use ◽

Paste Viscosity ◽

The Stability ◽

Viscosity Stability

To investigate the influences of quaternization/hydroxypropylsulfonation on viscosity stability, adhesion to fibers and film properties of oxidized tapioca starch (OTS) for ameliorating its end-use ability in applications such as warp-sizing and paper-making, a series of quaternized and hydroxypropylsulfonated OTS (QHOTS) samples were synthesized by simultaneous quaternization and hydroxypropylsulfonation of OTS with N-(3-chloro-2-hydroxypropyl) trimethylammonium chloride (CHPTAC) and 3-chloro-2-hydroxy-1-propanesulfonic acid sodium salt (CHPS-Na). The QHOTS granules were characterized by Fourier transform infra-red spectroscopic and scanning electron microscope techniques. Apparent viscosity and viscosity stability were determined, and adhesion was evaluated by measuring the bonding force of starch to the fibers. Film properties were also estimated in terms of tensile strength, breaking elongation, bending endurance, degree of crystallinity, and moisture regain. It was showed that quaternization/hydroxypropylsulfonation was capable of obviously improving viscosity stability of gelatinized OTS paste, enhancing bonding forces of OTS to cotton and polylactic acid (PLA) fibers, increasing breaking elongation, bending endurance and moisture regain of film and decreasing its tensile strength and degree of crystallinity, thereby obviously stabilizing paste viscosity, improving adhesion to fibers and lessening film brittleness. Increasing the level of quaternization/hydroxypropylsulfonation favored improvement in the stability, enhancement in adhesion and decrease in brittleness. The QHOTS showed potential in the applications of cotton and PLA sizing.

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A Novel Solution of Monitoring Incontinence Status by Conductive Yarn and Advanced Seamless Knitting Techniques

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892501200700415 ◽

2012 ◽

Vol 7 (4) ◽

pp. 155892501200700 ◽

Cited By ~ 2

Author(s):

Rong Liu ◽

Shuxiao Wang ◽

Terence T. Lao

Keyword(s):

Care Provider ◽

Electrical Resistance ◽

Conductive Yarns ◽

Wet Processing ◽

Potential Applications ◽

Stable Performance ◽

Seamless Knitting ◽

Intelligent Healthcare ◽

Conductive Yarn ◽

Product Dimension

This paper presents a novel solution for monitoring incontinence status through the design and development of the intelligent incontinence pants by the use of conductive yarns and incorporating advanced circular seamless knitting technology. The produced textile incorporates wire and electrodes by conductive yarn working with a siren system which can monitor, sense and alert the wearer and care provider on the incontinence status in real time so as to reduce the need for manual checking and minimize patient care workload. The engineered stitches, yarn materials, and unique seamless knitting techniques provide soft handling, special fabric mechanisms, and tactile comfort of the resulting product. The electrical resistance of knitted conductive yarn demonstrated a stable performance in wet processing. Fitting body trials were conducted to estimate product dimension and configuration. This study allows us to explore further the potential applications of conductive yarn and seamless knitting technology in bio-functional and intelligent healthcare products and solutions through integrating multidisciplinary knowledge and techniques.

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