Defect Structure of Diamond Film at the Interface with Amorphous Carbon

Diamond Crystals ◽

Transmission Electron ◽

Amorphous Carbon Layer

ABSTRACTDiamond films prepared by microwave plasma chemical vapor deposition, using a gas mixture of methane and hydrogen with ethanol, were formed on silicon substrates. Highresolution transmission electron microscopy was employed to characterize the microstructure at interface regions. It was found that the diamond crystals were grown on an amorphous carbon layer. Twins and stacking faults were observed at the regions interfaced with the amorphous carbon layer, suggesting that the defects may already exist in the nucleation stage and at the very first stage of growth. Also, some diamond nuclei embedded in the amorphous layer were observed.

Diamond Nucleation During Biased Chemical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-280-695 ◽

1992 ◽

Vol 280 ◽

Cited By ~ 1

Author(s):

Roseann Csencsits ◽

Janet Rankin ◽

Rachel E. Boekenhauer ◽

Michael K. Kundmann ◽

Brian W. Sheldon

Keyword(s):

Amorphous Carbon ◽

Vapor Deposition ◽

Microwave Plasma ◽

Carbon Film ◽

Chemical Vapor ◽

Amorphous Film ◽

Amorphous Layer ◽

Carbon Layer ◽

Diamond Nucleation

ABSTRACTThe initial stages of bias-enhanced chemical vapor deposition (CVD) of diamond were investigated in a microwave-plasma system. Samples were characterized with TEM and concurrent electron energy loss spectroscopy (EELS) to characterize chemical bonding in the deposited material. The results show that a thin amorphous carbon film is deposited during biasing, and that diamond nucleation occurs on this amorphous film. Isolated regions of crystalline SiC within the amorphous layer were also observed at longer bias times. These regions apparently form by a reaction between the amorphous carbon layer and the silicon substrate.

A Study of the Origin of Band-A Emission in Homoepitaxial Diamond Thin Films

MRS Proceedings ◽

10.1557/proc-588-87 ◽

1999 ◽

Vol 588 ◽

Author(s):

Daisuke Takeuchi ◽

Hideyuki Watanabe ◽

Sadanori Yamanaka ◽

Hideyo Okushi ◽

Koji Kajimura ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

High Resolution ◽

Grain Boundaries ◽

Microwave Plasma ◽

Diamond Films ◽

Chemical Vapor ◽

Transmission Electron ◽

Excitonic Emission

AbstractThe band-A emission (around 2.8 eV) observed in high quality (device-grade) homoepitaxial diamond films grown by microwave-plasma chemical vapor deposition (CVD) was studied by means of scanning cathodoluminescence spectroscopy and high-resolution transmission electron microscopy. Recent progress in our study on homoepitaxial diamond films was obtained through the low CH4/H2 conditions by CVD. These showed atomically flat surfaces and the excitonic emission at room temperature, while the band-A emission (2.95 eV) decreased. Using these samples, we found that the band-A emission only appeared at unepitaxial crystallites (UC) sites, while other flat surface parts still showed the excitonic emission. High-resolution transmission electron microscopy revealed that there were grain boundaries which contained π-bonds in UC. This indicates that one of the origin of the band-A emission in diamond films is attributed to π bonds of grain boundaries.

Microstructural evolution of diamond/Si(100) interfaces with pretreatments in chemical vapor deposition

10.1557/jmr.1995.3041 ◽

1995 ◽

Vol 10 (12) ◽

pp. 3041-3049 ◽

Cited By ~ 25

Author(s):

C.J. Chen ◽

L. Chang ◽

T.S. Lin ◽

F.R. Chen

Keyword(s):

Amorphous Carbon ◽

Vapor Deposition ◽

Microwave Plasma ◽

Chemical Vapor ◽

Carbon Layer ◽

Chemical Vapor Deposition Method ◽

Interfacial Region ◽

Cross Sectional ◽

Evolution Of Microstructure

Diamond was deposited on Si(100) substrates by the microwave plasma-assisted chemical vapor deposition method in three steps: carburization, biasing, and growth. High-resolution transmission electron microscopy in cross-sectional view has been used to observe the evolution of microstructures around the interfacial region between diamond and Si in each processing step. The chemistry near the interface was characterized with elemental mapping using an energy-filtered imaging technique with electron energy loss spectroscopy. An amorphous carbon layer, β-SiC and diamond particles, and graphite plates have been observed in the carburization stage. β-SiC can form in epitaxial orientation with Si in the following stage of biasing. Graphite and amorphous carbon were not observed after the bias was applied. Diamond grains were aligned in a strongly textured condition in the growth stage. It has been found that diamond, SiC, and Si all have (111) planes in parallel. The relation of the evolution of microstructure with the processing conditions is also discussed.

Aligned Carbon Nanotubes Via Microwave Plasma Enhanced Chemical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-593-39 ◽

1999 ◽

Vol 593 ◽

Cited By ~ 1

Author(s):

H. Cui ◽

D. Palmer ◽

O. Zhou ◽

B. R. Stoner

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Vapor Deposition ◽

Microwave Plasma ◽

Chemical Vapor ◽

Silicon Substrates ◽

Multi Wall Carbon Nanotubes ◽

Field Emission Properties ◽

Transmission Electron

ABSTRACTAligned multi-wall carbon nanotubes have been grown on silicon substrates by microwave plasma enhanced chemical vapor deposition using methane/ammonia mixtures. The concentration ratio of methane/ammonia in addition to substrate temperature was varied. The morphology, structure and alignment of carbon nanotubes were studied by scanning electron microscopy and transmission electron microscopy. Both concentric hollow and bamboo-type multi-wall carbon nanotubes were observed. Growth rate, size distribution, alignment, morphology, and structure of carbon nanotubes changed with methane/ammonia ratio and growth temperature. Preliminary results on field emission properties are also presented.

DEPOSITION AND CHARACTERIZATION OF NANOCRYSTALLINE DIAMOND FILMS ON MIRROR-POLISHED Si SUBSTRATE BY BIASED ENHANCED MICROWAVE PLASMA CHEMICAL VAPOR DEPOSITION

International Journal of Modern Physics B ◽

10.1142/s021797920201049x ◽

2002 ◽

Vol 16 (06n07) ◽

pp. 845-852

Author(s):

T. Soga ◽

T. Sharda ◽

T. Jimbo ◽

M. Umeno

Keyword(s):

Vapor Deposition ◽

Methane Concentration ◽

Microwave Plasma ◽

Chemical Vapor ◽

Nanocrystalline Diamond ◽

Silicon Substrates ◽

Si Substrate ◽

Plasma Chemical ◽

Plasma Chemical Vapor Deposition

Hard and smooth nanocrystalline diamond (NCD) thin films were deposited on polished silicon substrates by biased enhanced growth in microwave plasma chemical vapor deposition. The films deposited with varying the methane concentration and biasing voltage were characterized by Raman spectroscopy, nano-indenter, x-ray diffraction and atomic force microscopy. Stress in the films increases with decreasing methane concentration in the gas-phase and with increasing biasing. The adhesion between NCD film and Si substrate is very strong sustaining the compressive stress as high as high as 85 GPa. It was hypothesized that hydrogen content of the films and graphitic content of the films are responsible in generating stress. The hardness is well correlated with the Raman peak intensity ratio of NCD peak to G peak.

Flattened diamond crystals synthesized by microwave plasma chemical vapor deposition in a CO‐H2system

Journal of Applied Physics ◽

10.1063/1.356500 ◽

1994 ◽

Vol 75 (2) ◽

pp. 1151-1154 ◽

Cited By ~ 10

Author(s):

Keiji Hirabayashi ◽

Seiichiro Matsumoto

Keyword(s):

Vapor Deposition ◽

Microwave Plasma ◽

Chemical Vapor ◽

Plasma Chemical ◽

Diamond Crystals

Investigation of the low angle grain boundaries in highly oriented diamond films via transmission electron microscopy

10.1557/jmr.1994.2487 ◽

1994 ◽

Vol 9 (10) ◽

pp. 2487-2489 ◽

Cited By ~ 10

Author(s):

F.R. Sivazlian ◽

J.T. Glass ◽

B.R. Stoner

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Grain Boundary ◽

Microwave Plasma ◽

Chemical Vapor ◽

Plan View ◽

Transmission Electron ◽

Diffraction Patterns ◽

Defect Densities

Highly oriented diamond thin films grown on silicon via microwave plasma chemical vapor deposition were examined by transmission electron microscopy. In the plan view, defects appearing at the grain boundary were easily observed. (100) faceted grains that appeared to have coalesced were connected at their interfaces by dislocations characteristic of a low angle grain boundary. From Burgers vector calculations and electron diffraction patterns, the azimuthal rotation between grains was measured to be between 0 and 6°. The defect densities of these films are compared to reports from (100) textured randomly oriented films, and the relative improvement due to the reduction of misorientation and grain boundary angles is discussed.

Nucleation and growth during the chemical vapor deposition of diamond on SiO2 substrates

10.1557/jmr.1994.2164 ◽

1994 ◽

Vol 9 (8) ◽

pp. 2164-2173 ◽

Cited By ~ 20

Author(s):

Janet Rankin ◽

Rachel E. Boekenhauer ◽

Roseann Csencsits ◽

Yuzo Shigesato ◽

Matthew W. Jacobson ◽

...

Keyword(s):

Growth Kinetics ◽

Microwave Plasma ◽

Plasma Chemistry ◽

Chemical Vapor ◽

Fused Silica ◽

Diamond Growth ◽

Silicon Substrates ◽

Diamond Surfaces ◽

Nonlinear Growth ◽

Transmission Electron

The early stages of microwave-plasma assisted CVD of diamond on fused silica and silicon substrates were investigated. Nucleation densities on fused silica were somewhat lower than on silicon; however, the diamond growth rates on fused silica were faster. These results suggest that the substrate alters the plasma chemistry near the substrate. Transmission electron microscopy showed a relatively smooth interface between the diamond grains and the SiO2 surface. At low nucleation densities, the growth kinetics on both substrates were linear (i.e., the average feature size was proportional to the deposition time), which indicates that the growth kinetics were initially controlled by reaction(s) at the growing diamond surfaces. The transition to nonlinear growth kinetics observed at higher nucleation densities was probably caused by mass-transport limits.

Study of Carbon Films on Silicon Substrates

Materials Science Forum ◽

10.4028/www.scientific.net/msf.482.203 ◽

2005 ◽

Vol 482 ◽

pp. 203-206 ◽

Cited By ~ 1

Author(s):

O. Jašek ◽

M. Eliáš ◽

Z. Frgala ◽

Jiřina Matějková ◽

Antonín Rek ◽

...

Keyword(s):

Vapor Deposition ◽

Microwave Plasma ◽

Diamond Films ◽

Chemical Vapor ◽

Carbon Films ◽

Silicon Substrates ◽

Plasma Chemical ◽

Si Substrates

Carbon based films on silicon substrates have been studied by high resolution FE SEM equipped by an EDS analyzer. The first type are carbon nanotube (CNT) [1] films prepared on Si/SiO2 substrates with Ni or Fe layers by radiofrequency plasma chemical vapor deposition. Dependence of nanotube films properties on Ni and Fe thickness and deposition conditions have been studied. The second type of films discussed are microcrystalline and nanocrystalline diamond films grown on pre-treated Si substrates by microwave plasma chemical vapor deposition (MPCVD). The pre-treatment was varied and its effect on diamond films was studied.

Bombarding energy dependence of bonding structure in amorphous carbon interlayer and its effect on diamond nucleation

10.1557/jmr.1999.0274 ◽

1999 ◽

Vol 14 (5) ◽

pp. 2029-2035

Author(s):

U. C. Oh ◽

De Gang Cheng ◽

Fan Xiu Lu ◽

Jung Ho Je

Keyword(s):

Energy Dependence ◽

Amorphous Carbon ◽

Microwave Plasma ◽

Chemical Vapor ◽

Nucleation Density ◽

Diamond Nucleation ◽

Bonding Structure ◽

Sputtering Power ◽

Bombarding Energy

The bombarding energy dependence of bonding structure in amorphous carbon interlayer and its effect on diamond nucleation density (Nd) were studied. Amorphous carbon (a-C) interlayer was deposited by magnetron sputtering. Interestingly, the intensity ratio (ID/IG) of the D band (∼1400 cm−1) to the G band (∼1570 cm−1) in the Raman spectra and the optical band gap of the a-C film were found to be inversely proportional to the sputtering power, that is, to bombarding energy. When diamond was subsequently deposited at 800 °C by microwave plasma chemical vapor deposition (CVD), diamond could be grown only on the interlayers with higher ID/IG (≥2.20), and Nd was increased up to 2 × 106/cm2 with the increase of ID/IG ratio, that is, with the decrease of the bombarding energy. We experimentally confirmed that the amount of the sp3 bonded carbon clusters within the interlayer was dependent on the bombarding energy of the particles, determining the diamond nucleation density. We suggest that the transformation of the amorphous carbon into graphitic carbon should be effectively prevented for the diamond nucleation on the a-C interlayer.