A Carbon-Based Ultramicro-Thermocouple

2021 ◽  
Author(s):  
Olivia V. Scheibel ◽  
Mustafa Koz ◽  
Dieter M. Scheibel ◽  
Michael Schrlau
Keyword(s):  
Thermoelectric Power ◽  
Material Selection ◽  
Low Cost ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Carbon Layer ◽  
Manufacturing Method ◽  
Voltage Change ◽  
Thermal Sensing ◽  
Carbon Based

Abstract Micropipette-based thermocouples provide the advantage of a high tip diameter-to-length aspect ratio allowing the maintenance of a reference temperature crucial for accurate thermal sensing in microdomains. The research efforts in this field strive to achieve high thermoelectric power (voltage change per unit temperature change) while minimizing the sensing area, a pair of tasks that is by nature contradictory and thus, challenging. Herein, the design and fabrication of a carbon-based micropipette thermal sensor are described. A novel manufacturing method and set of materials are used to overcome the reduction in thermoelectric performance associated with small sensor sizes. A glass micropipette is utilized as a template in a chemical vapor deposition process to form a carbon layer in the lumen of the pipette. This carbon micropipette then serves as a scaffold on which gold and nickel are deposited, enabling the device to function as a thermocouple. This low-cost fabrication process results in a thermocouple with a sub-500 nm tip. The response of the thermocouple was characterized and demonstrated good repeatability in a temperature range of 0 to 60 °C. The unique material selection provided a thermoelectric power of 14.9 µV·K-1, a significant improvement (68%) relative to other micropipette-based thermocouples.

Low-Cost Sputtering Process for Carbon Nanotubes Synthesis

2019 ◽  
Vol 891 ◽  
pp. 195-199
Author(s):  
Theerapol Thurakitseree ◽  
Chupong Pakpum
Keyword(s):  
Carbon Nanotubes ◽  
Low Cost ◽  
Chemical Vapor ◽  
Thin Film Deposition ◽  
Deposition Process ◽  
Film Deposition ◽  
Synthesis Process ◽  
Metal Thin Films ◽  
Si Substrates ◽  
Custom Made

According to their wonderful properties, carbon nanotubes (CNTs) have been well known for decades. The synthesis process and catalyst deposition method have also drawn attention to control the nanotube structure and properties. Sputtering method is then one promising option to grow the nanotubes in mass production. This method is, however, still costly. Here, we have presented a simple low-cost custom-made DC magnetron sputtering for catalyst thin film deposition. Three different metal thin films (Fe, Ni, Cu) deposited on Si substrates have been employed to investigate nanotube production. Prior to deposition of the catalysts, Al was used as supporting layer. (Al/Fe, Al/Ni, Al/Cu). CNTs were grown by chemical vapor deposition process at 800°C. Ethanol was preliminary used as a carbon source. It was found that CNTs could be successfully grown from only Al/Ni catalysts in our system with the diameter of approximately 200 nm, where the rest of samples were not observed. In addition, vertical-aligned CNTs with the thickness of about 10 μm could be obtained when acetylene was replaced instead of ethanol with reducing partial pressure of the feedstock. A large D-band at 1338 cm-1 with broader G-band at 1582 cm-1 from Raman spectra give a rise to multi layers growth of sp2 carbon walls. Such dimension suggests that it is the characteristic of multi-walled carbon nanotubes.

Rapid Photo-Thermal Chemical Vapor Deposition of Amorphous Carbon From Diiodomethane

1999 ◽  
Vol 593 ◽  
Author(s):  
M. Lindstam ◽  
M. Boman ◽  
K. Piglmayer
Keyword(s):  
Electron Microscopy ◽  
Amorphous Carbon ◽  
High Efficiency ◽  
Low Cost ◽  
Substrate Surface ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Substrate Material ◽  
Halogen Lamp ◽  
X Ray

ABSTRACTA novel approach to deposit amorphous carbon from the precursor CH2I2 at low cost and high efficiency is reported. The combination of thermal and quantum photo effects shows new interesting growth behaviour. The radiation of a halogen-lamp was used to heat the substrate material and to split photolytically the precursor molecules above the substrate surface. The deposition process was investigated as a function of lamp power, gas phase partial pressures and substrate materials. The films were analysed by Raman spectroscopy, scanning electron microscopy, energy dispersive x-ray spectroscopy, x-ray photon spectroscopy, transmission electron microscopy and atomic force microscopy.

Synthesis, Properties and Applications of Superhard Amorphous Coatings

1995 ◽  
Vol 383 ◽  
Author(s):  
Michael A. Tamor
Keyword(s):  
Surface Engineering ◽  
Low Cost ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Hard Coatings ◽  
Low Friction ◽  
Capital Costs ◽  
Synthesis Properties ◽  
Improved Performance ◽  
Wear Coatings

ABSTRACTLow-friction/ultralow-wear coatings allow “surface engineering” for improved performance and durability, and enable use of new light weight or low cost materials. The accepted correlation of wear resistance with hardness suggests use of ceramic carbides and nitrides, with diamond being the ultimate anti-wear coating. While any of these may be deposited by chemical vapor deposition, the high cost (due to low deposition rates and high capital costs) and (usually) high deposition temperatures makes CVD coating impractical for cost-sensitive automotive applications. While rarely as hard as their crystalline counterparts, hard amorphous films exhibit similar (and occasionally superior) tribological properties and may be deposited on virtually any material at low cost. The highly nonequilibrium deposition process - conformal plasma reactive ion plating (CP-RIP) - allows tailoring of film properties and exploration of completely new compositions with no crystalline counterparts. Factors controlling the mechanical and optical properties of amorphous hard coatings, and recent progress in their application will be reviewed.

Template-Based Synthesis of Integrated Carbon Micro- and Nanostructures

2017 ◽  
Author(s):  
Olivia V. Scheibel ◽  
David Lanza ◽  
Michael G. Schrlau
Keyword(s):  
Vapor Deposition ◽  
Manufacturing Process ◽  
Low Cost ◽  
Chemical Vapor ◽  
Standard Laboratory ◽  
Laboratory Equipment ◽  
Carbon Structures ◽  
Nanofluidic Devices ◽  
Potential Applications ◽  
Carbon Based

This work demonstrates the manufacturing process of micro- and nanofluidic devices consisting of independent, aligned carbon pipes with potential applications as micro- and nanoscale dispensing systems, electrodes, and tools with which to study fundamental micro- and nanofluidics. A low-cost, high-throughput chemical vapor deposition (CVD) process was utilized to deposit carbon within novel silica-based templates. This simple template-based manufacturing process allows the carbon devices to be integrated into millimeter scale silica-based templates without micro- or nanoassembly, facilitating commercialization. Furthermore, the carbon-based devices were designed to readily integrate into standard laboratory equipment, promoting broad utilization. Herein, a repeatable methodology for fabricating multifunctional, carbon-based micro- and nanofluidic devices as well as establishing relationships between parameters at each stage of fabrication and the final geometry, including diameter and wall thickness of the carbon structures, of the device is presented.

scholarly journals Growth Mechanism of a Hybrid Structure Consisting of a Graphite Layer on Top of Vertical Carbon Nanotubes

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Nicolo' Chiodarelli ◽  
Cigang Xu ◽  
Olivier Richard ◽  
Hugo Bender ◽  
Alexander Klekachev ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Growth Conditions ◽  
Hybrid Structure ◽  
Carbon Layer ◽  
Time Dynamic ◽  
Catalyst Film ◽  
Optical And Electronic Properties ◽  
Deposition Processes

Graphene and carbon nanotubes (CNTs) are both carbon-based materials with remarkable optical and electronic properties which, among others, may find applications as transparent electrodes or as interconnects in microchips, respectively. This work reports on the formation of a hybrid structure composed of a graphitic carbon layer on top of vertical CNT in a single deposition process. The mechanism of deposition is explained according to the thickness of catalyst used and the atypical growth conditions. Key factors dictating the hybrid growth are the film thickness and the time dynamic through which the catalyst film dewets and transforms into nanoparticles. The results support the similarities between chemical vapor deposition processes for graphene, graphite, and CNT.

scholarly journals Stainless Steel Mesh Supported Carbon Nanofibers for Electrode in Bioelectrochemical System

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
Jing Wang ◽  
Ming Li ◽  
Fangtai Liu ◽  
Shuiliang Chen
Keyword(s):  
Stainless Steel ◽  
Carbon Nanofibers ◽  
High Performance ◽  
Carbon Nanofiber ◽  
Low Cost ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Bioelectrochemical System ◽  
Experimental Conditions ◽  
Direct Growth

We proposed a self-connected carbon nanofiber design for electrode in microbial bioelectrochemical system. This design was realized by direct growth of carbon nanofibers (CNFs) onto stainless steel (SSM) via a chemical vapor deposition process without addition of any external catalysts. In the CNFs-SSM composite electrode, the SSM acted as the conductive network and ensured efficient substrate and proton transfer, and the CNFs layer served as highly porous habitats for thick biofilm propagation. The current generated by the CNFs-SSM was 200 times higher than the bare SSM under the same experimental conditions. This provided a simple and promising method for preparation of electrode material with high performance and low-cost in bioelectrochemical system.

MOCVD OF SnO2 on Silicon Microhotplate Arrays for use un Gas Sensing Applications

1995 ◽  
Vol 415 ◽  
Author(s):  
F. Dimeo ◽  
S. Semancik ◽  
R.E. Cavicchi ◽  
J.S. Suehle ◽  
P. Chaparala ◽  
...  
Keyword(s):  
Thin Films ◽  
Gas Sensing ◽  
Low Cost ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Medical Diagnostics ◽  
Electrical Contacts ◽  
Quantitative Detection ◽  
Sensing Applications ◽  
Resistive Heater

ABSTRACTThe quantitative detection of gas concentrations in mixed atmospheres is becoming increasingly important in manufacturing processing, environmental monitoring, and medical diagnostics. Several conductive oxides, such as SnO2, ZnO, and TiO2, are well known to exhibit changes in resistivity when exposed to various gases at temperatures ranging from 200–500°C. Current discrete devices based on resistive changes such as the Taguchi sensor, however, suffer from certain performance problems, including poor gas detection specificity. Integrated arrays of sensors, fabricated using planar technology, offer a promising solution to these problems, as well as other benefits such as low power consumption and low cost.In this paper, we report the results of using Metalorganic Chemical Vapor Deposition (MOCVD) to fabricate thin films of SnO2 on microhotplate arrays. The studied arrays contain 4 micromachined, suspended elements, each having an integrated resistive heater that produces a rapid thermal rise time ∼3 msec. By separately heating individual elements, we can take advantage of the thermally selective nature of the MOCVD process to limit deposition to these areas, resulting in a maskless deposition process. In addition, these array elements have surface electrical contacts that permit the measurement of the resistance of the thin films during deposition, as well as when they are operated in a gas sensing mode. In situ growth measurements will be reported.

scholarly journals Rheological Issues in Carbon-Based Inks for Additive Manufacturing

Micromachines ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 99 ◽  
Author(s):  
Charlie O’Mahony ◽  
Ehtsham Ul Haq ◽  
Christophe Sillien ◽  
Syed A.M. Tofail
Keyword(s):  
Additive Manufacturing ◽  
Carbon Fibers ◽  
Carbon Materials ◽  
Low Cost ◽  
Complex Geometries ◽  
Flow Properties ◽  
Manufacturing Method ◽  
Commercial Market ◽  
Conductive Properties ◽  
Carbon Based

As the industry and commercial market move towards the optimization of printing and additive manufacturing, it becomes important to understand how to obtain the most from the materials while maintaining the ability to print complex geometries effectively. Combining such a manufacturing method with advanced carbon materials, such as Graphene, Carbon Nanotubes, and Carbon fibers, with their mechanical and conductive properties, delivers a cutting-edge combination of low-cost conductive products. Through the process of printing the effectiveness of these properties decreases. Thorough optimization is required to determine the idealized ink functional and flow properties to ensure maximum printability and functionalities offered by carbon nanoforms. The optimization of these properties then is limited by the printability. By determining the physical properties of printability and flow properties of the inks, calculated compromises can be made for the ink design. In this review we have discussed the connection between the rheology of carbon-based inks and the methodologies for maintaining the maximum pristine carbon material properties.

Reaction couples of ceramic thin films prepared by CVD

1988 ◽  
Vol 46 ◽  
pp. 798-799
Author(s):  
D.W. Susnitzky ◽  
S.R. Summerfelt ◽  
C.B. Carter
Keyword(s):  
Thin Film ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Solid State Reactions ◽  
Spatial Distributions ◽  
Diffusion Couples ◽  
Kinetics Studies ◽  
Ceramic Thin Films ◽  
Initial Stage

Solid-state reactions have traditionally been studied in the form of diffusion couples. This ‘bulk’ approach has been modified, for the specific case of the reaction between NiO and Al2O3, by growing NiAl2O4 (spinel) from electron-transparent Al2O3 TEM foils which had been exposed to NiO vapor at 1415°C. This latter ‘thin-film’ approach has been used to characterize the initial stage of spinel formation and to produce clean phase boundaries since further TEM preparation is not required after the reaction is completed. The present study demonstrates that chemical-vapor deposition (CVD) can be used to deposit NiO particles, with controlled size and spatial distributions, onto Al2O3 TEM specimens. Chemical reactions do not occur during the deposition process, since CVD is a relatively low-temperature technique, and thus the NiO-Al2O3 interface can be characterized. Moreover, a series of annealing treatments can be performed on the same sample which allows both Ni0-NiAl2O4 and NiAl2O4-Al2O3 interfaces to be characterized and which therefore makes this technique amenable to kinetics studies of thin-film reactions.

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