scholarly journals Controlled Geometry Formation of the Carbon Coils by the Substrate Pretreatment

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Semi Park ◽  
Sung-Hoon Kim
Keyword(s):  
Chemical Vapor Deposition ◽  
Reaction Time ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Si Substrate ◽  
Pretreatment Method ◽  
Thermal Chemical Vapor Deposition ◽  
Carbon Particles ◽  
Thermal Etching ◽  
Diamond Powders

Carbon coils could be synthesized using C2H2/H2 as source gases and SF6 as an incorporated additive gas under thermal chemical vapor deposition system. Prior to the carbon coils deposition reaction, the supporting substrates were pretreated using various methods. Among the methods, the thermal etching pretreatment of Ni-SiO2 substrate with SF6 leads to the exclusive formation of the nanosized carbon coils. The diamond powders pretreatment of Si substrate gives rise to the dominant formation of the microsized carbon coils after 10 minutes reaction time. The geometry selectivity for the carbon coils in a specific pretreatment method was discussed in association with the peeled-off Ni layers by the thermal etching pretreatment with SF6 and the remained carbon particles on Si substrate by the diamond powders pretreatment.

scholarly journals Effect of Si and SiO2Substrates on the Geometries of As-Grown Carbon Coils

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Semi Park ◽  
Sung-Hoon Kim ◽  
Tae-Gyu Kim
Keyword(s):  
Thin Film ◽  
Thermal Expansion ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Quartz Substrate ◽  
Substrate Surface ◽  
Chemical Vapor ◽  
Si Substrate ◽  
Thermal Chemical Vapor Deposition ◽  
Surface Morphologies

Carbon coils could be synthesized using C2H2/H2as source gases and SF6as an incorporated additive gas under thermal chemical vapor deposition system. Si substrate, SiO2thin film deposited Si substrate (SiO2substrate), and quartz substrate were employed to elucidate the effect of substrate on the formation of carbon coils. The characteristics (formation densities, morphologies, and geometries) of the deposited carbon coils on the substrate were investigated. In case of Si substrate, the microsized carbon coils were dominant on the substrate surface. While, in case of SiO2substrate, the nanosized carbon coils were prevailing on the substrate surface. The surface morphologies of samples were investigated step by step during the reaction process. The cause for the different geometry formation of carbon coils according to the different substrates was discussed in association with the different thermal expansion coefficient values of Si and SiO2substrates and the different etched characteristics of Si and SiO2substrates by SF6 + H2flow.

Deposition of Monolayer-Scale Germanium/Silicon Heterostructures by Rapid Thermal Chemical Vapor Deposition

1994 ◽  
Vol 342 ◽  
Author(s):  
A. St. Amour ◽  
J.C. Sturm
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Molecular Beam ◽  
Chemical Vapor ◽  
Si Substrate ◽  
Thermal Chemical Vapor Deposition ◽  
Cvd Growth ◽  
First Time ◽  
Germanium Silicon ◽  
Silicon Heterostructures

ABSTRACTDeposition of monolayer scale Ge/Si heterostructures by Rapid Thermal Chemical Vapor Deposition has been achieved for the first time. All previous work in this area was by Molecular Beam Epitaxy. We have observed the change in Ge growth rate at 500°C as the Si substrate was covered by the first monolayer of Ge. Auger Electron Spectroscopy and Raman scattering experiments determined that the CVD growth mode for Ge on Si (100) at 550°C is Stranski-Krastanov, with the transition to islanding occurring after three monolayers.

Formation of β‐SiC at the interface between an epitaxial Si layer grown by rapid thermal chemical vapor deposition and a Si substrate

1990 ◽  
Vol 67 (4) ◽  
pp. 2176-2179 ◽  
Author(s):  
Ki‐Bum Kim ◽  
Philippe Maillot ◽  
Alan E. Morgan ◽  
Ahmad Kermani ◽  
Yen‐Hui Ku
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Si Substrate ◽  
Thermal Chemical Vapor Deposition

scholarly journals Research on the Preparation and Spectral Characteristics of Graphene/TMDs Hetero-structures

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Tao Han ◽  
Hongxia Liu ◽  
Shulong Wang ◽  
Shupeng Chen ◽  
Kun Yang
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Spectral Characteristics ◽  
Graphene Film ◽  
Chemical Vapor ◽  
Chemical Vapor Deposition Method ◽  
Si Substrate ◽  
Broadband Absorption ◽  
Gate Effect ◽  
Pressure Chemical

AbstractThe Van der Waals (vdWs) hetero-structures consist of two-dimensional materials have received extensive attention, which is due to its attractive electrical and optoelectronic properties. In this paper, the high-quality large-size graphene film was first prepared by the chemical vapor deposition (CVD) method; then, graphene film was transferred to SiO2/Si substrate; next, the graphene/WS2 and graphene/MoS2 hetero-structures were prepared by the atmospheric pressure chemical vapor deposition method, which can be achieved by directly growing WS2 and MoS2 material on graphene/SiO2/Si substrate. Finally, the test characterization of graphene/TMDs hetero-structures was performed by AFM, SEM, EDX, Raman and PL spectroscopy to obtain and grasp the morphology and luminescence laws. The test results show that graphene/TMDs vdWs hetero-structures have the very excellent film quality and spectral characteristics. There is the built-in electric field at the interface of graphene/TMDs heterojunction, which can lead to the effective separation of photo-generated electron–hole pairs. Monolayer WS2 and MoS2 material have the strong broadband absorption capabilities, the photo-generated electrons from WS2 can transfer to the underlying p-type graphene when graphene/WS2 hetero-structures material is exposed to the light, and the remaining holes can induced the light gate effect, which is contrast to the ordinary semiconductor photoconductors. The research on spectral characteristics of graphene/TMDs hetero-structures can pave the way for the application of novel optoelectronic devices.

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