scholarly journals Stability Observations and Surface Analysis of Air Fired Nickel Thick Film Conductors

1985 ◽  
Vol 11 (4) ◽  
pp. 291-297 ◽  
Author(s):  
R. B. Pranchov ◽  
D. S. Campbell
Keyword(s):  
Thick Film ◽  
Surface Analysis ◽  
Glass Phase ◽  
Film Surface ◽  
Peak Temperature ◽  
Film Material ◽  
Film Instability ◽  
Isotropic Distribution ◽  
Possible Cause ◽  
High Instability

The results from an investigation of the properties of air fired Nickel thick film produced with conductive paste ESL 2554 on 96% Al2O3substrates are described. The analysis of the possible causes of instability of this thick film material has been done using the methods of surface analysis. The picture of the film surface structure obtained as a result of surface analysis shows a non-isotropic distribution of the metal and glass phase. For a firing peak temperature of 650℃ there is little nickel present at the film surface, and this could be the main cause of the high instability and low adhesion observed. To obtain a stable film the maximum firing peak temperature has been established at 580℃. This has been confirmed by comparing the surface analysis results from films prepared at 650℃ and 580℃ peak temperatures.The surface analysis of the substrate shows the presence of Silicon which may be considered as another possible cause of film instability.

New thick-film material for piezoresistive sensors

2001 ◽  
Vol 95 (1) ◽  
pp. 39-45 ◽  
Author(s):  
S. Tankiewicz ◽  
B. Morten ◽  
M. Prudenziati ◽  
L.J. Golonka
Keyword(s):  
Thick Film ◽  
Film Material ◽  
Piezoresistive Sensors

Characterization of Diamond Spherical Shell Thick Film by DC Plasma CVD

2008 ◽  
Vol 375-376 ◽  
pp. 216-220 ◽  
Author(s):  
Duo Sheng Li ◽  
Dun Wen Zuo ◽  
Yu Li Sun ◽  
Rong Fa Chen ◽  
Wen Zhuang Lu ◽  
...  
Keyword(s):  
Spherical Shell ◽  
Thick Film ◽  
Diamond Film ◽  
Substrate Surface ◽  
Film Surface ◽  
Growth Surface ◽  
Dc Plasma ◽  
Force Microscopy ◽  
Microstructure Morphology

Diamond spherical shell thick film was prepared by high power DC-plasma jet CVD. Atom force microscopy, scanning electron microscopy, Raman spectroscopy and roughness-profile-meter were used to characterize microstructure, morphology, impurities and orientation evolution of diamond spherical shell thick film. The results show that, when nucleation begins, grains grow random orientation. The grain size of spherical diamond film prepared is compact, clear, uniform, continuous and no remarkable bigger grain over the whole surface of film. On the growth surface, (100) facets were dominant, and the cross-section SEM indicated that film columnar spreading grew from the substrate surface to the diamond film surface. The roughness of the growth surface was much more than that of the nucleation surface. To adjust some important parameters as methane concentrate, depositing time, and matrix temperature, and high quality diamond spherical shell thick film was deposited.

Piezoelectric Paint: Thick-Film Sensors for Structural Monitoring of Shock and Vibration

Volume 3 ◽  
2004 ◽  
Author(s):  
J. M. Hale
Keyword(s):  
Thick Film ◽  
Dynamic Range ◽  
Strain Sensors ◽  
Structural Monitoring ◽  
Dynamic Strain ◽  
Environmental Damage ◽  
Film Material ◽  
Significant Deterioration ◽  
Vibration Sensors ◽  
Paint Spray

This paper describes dynamic strain sensors made using piezoelectric paint, a novel piezoelectric thick-film material which can be deposited using conventional paint spray equipment. The morphology of piezoelectric paint is described briefly, followed by a fuller description of the characteristics of thick-film vibration sensors made using it. It is shown that they have adequate properties (dynamic range and bandwidth) for use in structural monitoring applications, and that they are robust against environmental damage. Finally, a field trial is described in which a sensor has survived for three years without significant deterioration in a typical location on a bridge.

High Performance Etchable RoHS Compliant Thick Film Gold Conductor

2018 ◽  
Vol 2018 (1) ◽  
pp. 000620-000627 ◽  
Author(s):  
Samson Shahbazi ◽  
Gregg Berube ◽  
Stephanie Edwards ◽  
Ryan Persons ◽  
Caitlin Shahbazi
Keyword(s):  
Thick Film ◽  
High Performance ◽  
Failure Modes ◽  
High Reliability ◽  
Film Surface ◽  
Wire Bonding ◽  
Aluminum Wire ◽  
Sem Images ◽  
Lead And Cadmium ◽  
Wire Bond

Abstract The thick film paste manufacturers are expected to produce conductors which are lead and cadmium free, yet have excellent fired film properties and the same performance and properties as the cadmium and lead containing formulations. The fired film surface of these conductors must be defect free (i.e. imperfections, pills, agglomerates) after multiple firing steps and must perform on dielectric as well as substrates from different suppliers. Typically, the thick film gold conductors are used in high reliability applications such as medical devices, military applications, and high frequency circuits, which require robust performance at high and low temperatures, in chemically aggressive environments, or extremely humid conditions. As circuits decrease in size and become more complex, the thick film gold properties become increasingly critical. The challenge is to develop an alternative gold conductor formulation, which can print and resolve fine features (down to 4 mil lines and spaces) as well as have the ability to be etched for higher density circuit designs (down to 1–2 mil lines and spaces). Gold conductors are typically used in conjunction with other high temperature thick films so good performance after multiple firings was also a targeted requirement. Heraeus has been proactive for the past decade in the development of thick film products that are both RoHS (lead and cadmium free) as well as REACH compliant. This paper discusses the experiments that were performed in order to understand the contribution of gold powder, organic and inorganic system to improve the fired film performance. These formulations were compared against existing gold conductors including the high performance gold conductor options as well as other available standard gold conductor options. Thin wire bonding trials including both gold and aluminum wire are used to compare influences of raw materials which includes high volume wire bonding reliability including failure modes and aged wire bond adhesion at elevated temperature exposures (300°C) for extended periods of time. In order to analyze fired film morphology and link this up to wire bond performance, SEM images of the conductor surface and cross sections were conducted. These studies resulted in a newly developed thick film gold conductor paste for use in a wide variety of applications. We present wire-bonding data with gold and aluminum wire and reliability results on both 96% Al2O3 ceramic substrates as well as on top of standard dielectrics.

Unified approach to tear film surface analysis with high-speed videokeratoscopy

2019 ◽  
Vol 36 (4) ◽  
pp. B15 ◽  
Author(s):  
Clara Llorens-Quintana ◽  
Dorota H. Szczesna-Iskander ◽  
D. Robert Iskander
Keyword(s):  
Surface Analysis ◽  
High Speed ◽  
Tear Film ◽  
Film Surface ◽  
Unified Approach

scholarly journals Comparison of Enameled Steel Substrate Properties for Thick Film Use

1980 ◽  
Vol 7 (1-3) ◽  
pp. 55-62 ◽  
Author(s):  
S. J. Stein ◽  
C. Huang ◽  
A. S. Gelb
Keyword(s):  
Thick Film ◽  
Steel Substrate ◽  
Soda Lime ◽  
Dissipation Factor ◽  
Soda Lime Glass ◽  
Film Material ◽  
Insulation Resistance ◽  
Large Area ◽  
Substrate Properties ◽  
Steel Substrates

Porcelain enameled steels have had a long history of industrial, structural and related applications. Recent interest in such materials has centered on electrical uses as a substrate for hybrid circuits, additive printed wiring, and packaging. A study of some of the critical properties of available enameled steels was undertaken.Five types of enameled steel substrates from three manufacturers were tested. The electrical properties studied included dielectric constant, dissipation factor, voltage breakdown, surface and bulk insulation resistance. The effect of humidity on the insulation resistance of the enamel coatings themselves was compared. The influence of the thermal conductivity of the substrates was also examined.The properties of a thick film resistor system was determined on the various enamel steel substrates. The properties tested included resistivity and TCR firing sensitivity.The effect of the type of substrate on the properties of a selection of thick film conductors was determined. Conductivity and gold and aluminum wire bond strength were compared on the various substrates.The dielectric properties of a multilayer/crossover dielectric thick film material were compared among 96% alumina, soda-lime glass and the various enameled steel substrates.Many individual differences between the enameled steel substrates were found. However, all of the substrates could be utilized to produce satisfactory thick film circuits when the proper choice of thick film materials was made.Continuing changes, improvements and additional sources of supply are expected to overcome some of the present shortcomings. These should enhance the use of such substrates for large area uses and lower cost applications.

Synthesis, Characterization and Application of Thin Film Carbon Nanotube Material

2000 ◽  
Vol 633 ◽  
Author(s):  
Alexander N. Obraztsov ◽  
Alexander P. Volkov
Keyword(s):  
Thin Film ◽  
Multiwall Carbon Nanotubes ◽  
Film Surface ◽  
Chemical Vapor ◽  
Film Material ◽  
Light Emitting ◽  
Light Emitting Devices ◽  
Low Field ◽  
Predominant Orientation ◽  
Graphite Basal Plane

AbstractThe non-catalytical chemical vapor deposition (CVD) method was used to grow carbon thin film material consisting of plate-like nanosized graphite crystallites and multiwall carbon nanotubes with predominant orientation of both species by their crystallographic plane, corresponding to a graphite basal plane, along a normal to the film surface. A number of experimental techniques was used for examination and characterization of the film phase composition, morphology, and electron properties peculiarities. Low-field electron emission with highly density of emission sites and emission current was obtained for the film material and allow to demonstrate their applicability for sealed prototypes of light-emitting devices.

Fabrication of Bi2-xSbxTe3 (x=0-1.5) Thick Film by Centrifugal Deposition

2007 ◽  
Vol 561-565 ◽  
pp. 519-522 ◽  
Author(s):  
T. Aoki ◽  
Yoshiaki Kinemuchi ◽  
Hisashi Kaga ◽  
Chihiro Ito ◽  
Hirohide Ishiguro ◽  
...  
Keyword(s):  
Single Crystal ◽  
Thick Film ◽  
Thermoelectric Properties ◽  
High Efficiency ◽  
Film Surface ◽  
Thermoelectric Power Factor ◽  
Thermoelectric Element ◽  
Degree Of Orientation ◽  
Low X ◽  
P Type

A Bi2-xSbxTe3(x=0-1.5) thick film thermoelectric element was fabricated using centrifugal deposition and its Sb content-dependent thermoelectric properties were investigated. When the Sb content was low (x=0.5), two types of fine structure along the direction of the thickness were observed. Pole figure measurements revealed that the vicinity of the film surface was composed of single crystal layers oriented along the c-axis and the vicinity of the interface with the substrate was composed of randomly orientated layers. As the content of Sb increased, the degree of orientation improved, and at x=1.5 the entire film was close to a single crystal. A Bi0.5Sb1.5Te3 thick film showed p-type thermoelectric properties and a thermoelectric power factor of 3.5 ×10-3W/mK2. It was thus demonstrated that centrifugal deposition can be used to fabricate thermoelectric elements with high efficiency.

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