Catalyst-Less and Transfer-Less Synthesis of Graphene on Si(100) Using Direct Microwave Plasma Enhanced Chemical Vapor Deposition and Protective Enclosures

In this study, graphene was synthesized on the Si(100) substrates via the use of direct microwave plasma-enhanced chemical vapor deposition (PECVD). Protective enclosures were applied to prevent excessive plasma etching of the growing graphene. The properties of synthesized graphene were investigated using Raman scattering spectroscopy and atomic force microscopy. Synthesis time, methane and hydrogen gas flow ratio, temperature, and plasma power effects were considered. The synthesized graphene exhibited n-type self-doping due to the charge transfer from Si(100). The presence of compressive stress was revealed in the synthesized graphene. It was presumed that induction of thermal stress took place during the synthesis process due to the large lattice mismatch between the growing graphene and the substrate. Importantly, it was demonstrated that continuous horizontal graphene layers can be directly grown on the Si(100) substrates if appropriate configuration of the protective enclosure is used in the microwave PECVD process.

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Effects of methane gas flow rate on the optoelectrical properties of nitrogenated carbon thin films grown by surface wave microwave plasma chemical vapor deposition

Diamond and Related Materials ◽

10.1016/j.diamond.2005.07.034 ◽

2006 ◽

Vol 15 (2-3) ◽

pp. 371-377 ◽

Cited By ~ 21

Author(s):

M. Rusop ◽

S. Adhikari ◽

A.M.M. Omer ◽

T. Soga ◽

T. Jimbo ◽

...

Keyword(s):

Thin Films ◽

Chemical Vapor Deposition ◽

Surface Wave ◽

Vapor Deposition ◽

Gas Flow ◽

Microwave Plasma ◽

Chemical Vapor ◽

Gas Flow Rate ◽

Plasma Chemical ◽

Plasma Chemical Vapor Deposition

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(110)-oriented diamond films synthesized by microwave chemical-vapor deposition

Journal of Materials Research ◽

10.1557/jmr.1990.2469 ◽

1990 ◽

Vol 5 (11) ◽

pp. 2469-2482 ◽

Cited By ~ 44

Author(s):

Koji Kobashi ◽

Kozo Nishimura ◽

Koichi Miyata ◽

Kazuo Kumagai ◽

Akimitsu Nakaue

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Microwave Plasma ◽

Hydrogen Plasma ◽

Diamond Films ◽

Film Surface ◽

Chemical Vapor ◽

Hydrogen Gas ◽

X Ray ◽

Bilayer Films

Bilayer diamond films were deposited on Si substrates by microwave-plasma chemical-vapor deposition (CVD) using a methane-hydrogen gas mixture. The first layer was deposited for 3 h using a reaction gas which was composed of 2.5 vol. % methane and 97.5 vol.% hydrogen. The deposited film consisted of very weakly (110)-oriented microcrystalline diamonds as well as amorphous carbon and graphite. In order to remove non-diamond carbons from the film surface, the specimen was treated in hydrogen plasma for 1 h. Finally, a second layer was deposited on the first layer for 14 h using a methane concentration of between 0.2 and 1.6 vol.%. It was found that the x-ray intensity of the (220) diffraction of the bilayer films was much greater than that of the (111) diffraction, indicating that the diamond grains in the second layer were strongly oriented with their crystallographic (110) planes parallel to the substrate surface. X-ray diffraction spectra of bilayer films in which the second layer was deposited for 7, 14, 21, and 35 h using two different methane concentrations, 0.3 and 1.2 vol.%, showed that within periods of up to 21 h, the (220) intensity increased with the deposition time much more quickly than the (111) intensity, indicating that the degree of (110) orientation was further enhanced as the second layer thickness increased. However, the (220) intensity decreased after 21 h, presumably due to thermal randomization. Results of scanning electron microscopy, electron diffraction, and Raman spectroscopy of the bilayer films are also presented.

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Chemical Vapor Deposition of Boron Phosphide Thin Films

MRS Proceedings ◽

10.1557/opl.2012.1030 ◽

2012 ◽

Vol 1432 ◽

Cited By ~ 2

Author(s):

Julia K.C. Abbott ◽

J. Daniel Brasfield ◽

Philip D. Rack ◽

Gerd J. Duscher ◽

Charles S. Feigerle

Keyword(s):

Thin Films ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Atmospheric Pressure ◽

Lattice Mismatch ◽

Chemical Vapor ◽

Hydrogen Gas ◽

Electron Hole ◽

Boron Phosphide ◽

Image Position

ABSTRACTBoron Phosphide (BP) is a promising material for use as a room temperature semiconductor detector of thermal neutrons. The absorption of a thermal neutron by a 10B nucleus in BP can yield 2.3MeV of energy which in solid state BP can yield ∼0.5 million electron-hole pairs that would be detectable with minimal amplification in a device. BP thin films are grown according to the net reaction below in a cold wall chemical vapor deposition (CVD) reactor: Thin film depositions are performed using diborane and phosphine with a balance of hydrogen gas at near atmospheric pressure with RF induction heating. The resultant BP films are characterized by Raman, XRD, SEM, TEM and TEM-EELS for chemical composition, surface and bulk morphology. BP growths on Si and SiC substrates are compared. SiC provides reduced lattice mismatch for growth of BP and growth of heteroepitaxial BP on SiC will be discussed.

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Efficiency of methane and acetylene in forming diamond by microwave plasma assisted chemical vapor deposition

Journal of Materials Research ◽

10.1557/jmr.1992.1427 ◽

1992 ◽

Vol 7 (6) ◽

pp. 1427-1431 ◽

Cited By ~ 41

Author(s):

Curtis E. Johnson ◽

Wayne A. Weimer ◽

Frank M. Cerio

Keyword(s):

Chemical Vapor Deposition ◽

Flow Rate ◽

Vapor Deposition ◽

Gas Flow ◽

Microwave Plasma ◽

Chemical Vapor ◽

Diamond Growth ◽

Exhaust Gas ◽

Methyl Radical ◽

Gaseous Products

Diamond films were grown by microwave plasma assisted chemical vapor deposition using mixtures of 1% 13CH4 and 0.5% 12C2H2 in H2, and stable gaseous products were analyzed by mass spectrometry. The major gaseous products are methane and acetylene, and scrambling of the 13C label can be controlled at relatively high gas flow rates. At the highest flow rate studied a diamond film was grown with 77% 13C incorporation, while the methane in the reactor exhaust gas at this flow rate contained 83% 13C. By comparing gaseous 13C compositions with that of the films, the efficiency of diamond growth from methane (possibly via the methyl radical) is estimated to be about ten times higher than that for acetylene.

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Properties of hydrogenated amorphous silicon carbide films prepared at various hydrogen gas flow rates by hot-wire chemical vapor deposition

Thin Solid Films ◽

10.1016/j.tsf.2005.07.186 ◽

2006 ◽

Vol 501 (1-2) ◽

pp. 177-180 ◽

Cited By ~ 12

Author(s):

M. Mori ◽

A. Tabata ◽

T. Mizutani

Keyword(s):

Silicon Carbide ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Gas Flow ◽

Hydrogenated Amorphous Silicon ◽

Chemical Vapor ◽

Hydrogen Gas ◽

Hot Wire ◽

Flow Rates ◽

Hydrogenated Amorphous

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An Investigation on the Formation of Carbon Nanotubes by Two-Stage Chemical Vapor Deposition

Journal of Nanomaterials ◽

10.1155/2012/972126 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5 ◽

Cited By ~ 8

Author(s):

M. S. Shamsudin ◽

M. F. Achoi ◽

M. N. Asiah ◽

L. N. Ismail ◽

A. B. Suriani ◽

...

Keyword(s):

Carbon Nanotubes ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Pyrolysis Temperature ◽

Sol Gel ◽

Chemical Vapor ◽

Synthesis Process ◽

Two Stage ◽

Synthesis Time ◽

Custom Made

High density of carbon nanotubes (CNTs) has been synthesized from agricultural hydrocarbon: camphor oil using a one-hour synthesis time and a titanium dioxide sol gel catalyst. The pyrolysis temperature is studied in the range of 700–900°C at increments of 50°C. The synthesis process is done using a custom-made two-stage catalytic chemical vapor deposition apparatus. The CNT characteristics are investigated by field emission scanning electron microscopy and micro-Raman spectroscopy. The experimental results showed that structural properties of CNT are highly dependent on pyrolysis temperature changes.

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Role of oxygen in the growth of carbon nanotubes on metal alloy fibers by plasma-enhanced chemical vapor deposition

Journal of Materials Research ◽

10.1557/jmr.2009.0174 ◽

2009 ◽

Vol 24 (4) ◽

pp. 1536-1542 ◽

Cited By ~ 3

Author(s):

Young Kyun Moon ◽

Chang Goo Jung ◽

Seok Joo Park ◽

Tae Gyu Kim ◽

Soo H. Kim

Keyword(s):

Carbon Nanotubes ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Gas Flow ◽

Microwave Plasma ◽

Chemical Vapor ◽

Deposition Process ◽

Growth Time ◽

Metal Mesh ◽

Fibrous Metal

A method allowing for the stable growth of carbon nanotubes (CNTs) on the surface of a fibrous metal mesh substrate (SUS304) was developed with the assistance of the microwave plasma-enhanced chemical vapor deposition process. The controlled addition of up to ∼13% of O2 to the CH4 plasma reacting gas flow was found to promote the growth of the CNTs by oxidizing the amorphous carbon and removing the active H2 radicals. However, excessive amounts of O2 (i.e., fraction of O2 > ∼13%) and H2 were found to play a negative role in the growth of the CNTs. The control of the density and length of the CNTs was also achieved by varying the H2 plasma reduction time and CH4 plasma reacting time, respectively. Longer H2 reduction pretreatment of the catalytic metal islands resulted in the formation of a less dense CNT forest with craters. When the growth time of the CNTs was increased to ∼20 min, their length was increased to ∼10 μm. However, when the growth time of the CNTs exceeded 20 min, their length was significantly decreased, indicating that the continuous presence of O2 in the CH4 plasma destroys the preformed CNTs due to the oxidation reaction.

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