Surface Preparation of Single Crystal C(001) Substrates for Homoepitaxial Diamond Growth

ABSRACTA novel substrate preparation procedure which can be employed to remove the original surface from as-received C(001) natural diamond substrates has been developed. A description of the various substrate processing steps which includes, low-energy ion implantation of C and O, high-temperature annealing, electrochemical etching and surface plasmas treatments is presented. Also demonstrated is the growth of topographically excellent homoepitaxial films by rf-plasma-enhanced chemical vapor deposition using water/ethanol mixtures on C(001) substrates.

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Characterization of epitaxial diamond on natural diamond substrates by cathodoluminescence

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148903 ◽

1993 ◽

Vol 51 ◽

pp. 614-615

Author(s):

D.P. Malta ◽

E.A. Fitzgerald ◽

J.B. Posthill ◽

R.A. Rudder ◽

G.C. Hudson ◽

...

Keyword(s):

Natural Diamond ◽

Chemical Vapor ◽

Wide Band ◽

Growth Conditions ◽

Diamond Growth ◽

Wide Band Gap ◽

Type Ia ◽

Large Effort ◽

Surface Morphologies

A large effort continues in the development of diamond growth technologies for the production of electronic-grade diamond epitaxy. Diamond has several properties such as a wide band gap (5.48 eV) and high thermal conductivity (2000 W m-1K-1) that make it desirable for electronic applications. Characterization of diamond with cathodoluminescence (CL) spectroscopy yields information on impurity and defect distributions with both spatial and energy resolution, providing insight into the growth process.Diamond films were grown by plasma-enhanced chemical vapor deposition (PECVD) on natural type Ia 1mm × 1mm × 0.25mm diamond substrates. The results of microstructural studies on this type substrate are discussed elsewhere in these proceedings. Two films were selected for CL analysis based on their strikingly different surface morphologies but similar growth conditions. Both were grown for 6 hours at a substrate temperature of ∽ 750°C and a pressure of 5 Torr. The gas mixtures were varied: CO/CH4/H2 was used in one case and CH4/H2 in the other.

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Fabrication of a Free-Standing, Synthetic, Single Crystal Diamond Plate Using Ion Implantation and Plasma-Enhanced Chemical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-388-299 ◽

1995 ◽

Vol 388 ◽

Cited By ~ 1

Author(s):

J.B. Posthill ◽

D.P. Malta ◽

T.P. Humphreys ◽

G.C. Hudson ◽

R.E. Thomas ◽

...

Keyword(s):

Single Crystal ◽

Electrochemical Etching ◽

Chemical Vapor ◽

Growth Conditions ◽

Diamond Growth ◽

Free Standing ◽

Diamond Plate ◽

Single Crystal Diamond ◽

Type Ia ◽

Lift Off

AbstractUsing a specific combination of energetic and chemical processes we have grown homoepitaxial diamond on and lifted it off of a type Ia natural C(100) crystal. Before growth, the C(100) crystal is exposed to a self implant of 190keV energy and dose of 1E16 cm-2. Low temperature (~600°C) homoepitaxial diamond growth conditions were used that are based on water-alcohol source chemistries. To achieve layer separation (lift-off), samples were annealed to a temperature sufficient to graphitize the buried implant-damaged region. Contactless electrochemical etching was found to remove the graphite, and a transparent synthetic (100) single crystal diamond plate of 17.5μm thickness was lifted off. This free-standing diamond single crystal plate was characterized and found to be comparable to homoepitaxial films grown on unimplanted single crystal diamond.

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Fracture strength measurement of filament assisted CVD polycrystalline diamond films

Journal of Materials Research ◽

10.1557/jmr.1992.1432 ◽

1992 ◽

Vol 7 (6) ◽

pp. 1432-1437 ◽

Cited By ~ 34

Author(s):

G.F. Cardinale ◽

C.J. Robinson

Keyword(s):

Fracture Strength ◽

Microwave Plasma ◽

Natural Diamond ◽

Diamond Films ◽

Chemical Vapor ◽

Polycrystalline Diamond ◽

High Strength ◽

Coarse Grained ◽

Diamond Growth ◽

Growth Surface

The fracture strength of polycrystalline diamond films deposited by filament assisted chemical vapor deposition in the thickness range of 3.5 to 160 μm is investigated. Using a burst pressure technique, the fracture strengths of circular diamond film specimens are calculated. An average fracture strength of 730 MPa for nine samples was computed. This value is in good agreement with published strengths of microwave plasma deposited diamond films, comparable to other high strength materials, and within an order of magnitude of the fracture strength of bulk natural diamond. The average fracture strength of the fine-grained substrate interface appears consistently higher than that of the coarse-grained diamond growth surface.

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Characterization of homoepitaxial diamond films by Electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100088713 ◽

1991 ◽

Vol 49 ◽

pp. 880-881

Author(s):

D.P. Malta ◽

S.A. Willard ◽

R.A. Rudder ◽

G.C. Hudson ◽

J.B. Posthill ◽

...

Keyword(s):

Electron Microscopy ◽

Surface Defects ◽

Substrate Surface ◽

Diamond Films ◽

Chemical Vapor ◽

Polycrystalline Diamond ◽

Large Degree ◽

Rf Plasma ◽

Semiconducting Diamond

Semiconducting diamond films have the potential for use as a material in which to build active electronic devices capable of operating at high temperatures or in high radiation environments. A major goal of current device-related diamond research is to achieve a high quality epitaxial film on an inexpensive, readily available, non-native substrate. One step in the process of achieving this goal is understanding the nucleation and growth processes of diamond films on diamond substrates. Electron microscopy has already proven invaluable for assessing polycrystalline diamond films grown on nonnative surfaces.The quality of the grown diamond film depends on several factors, one of which is the quality of the diamond substrate. Substrates commercially available today have often been found to have scratched surfaces resulting from the polishing process (Fig. 1a). Electron beam-induced current (EBIC) imaging shows that electrically active sub-surface defects can be present to a large degree (Fig. 1c). Growth of homoepitaxial diamond films by rf plasma-enhanced chemical vapor deposition (PECVD) has been found to planarize the scratched substrate surface (Fig. 1b).

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The value of Electron Microscope studies of imperfect natural diamonds

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100174102 ◽

1990 ◽

Vol 48 (4) ◽

pp. 194-195

Author(s):

J C Walmsley ◽

A R Lang

Keyword(s):

Electron Microscope ◽

Classification Scheme ◽

Natural Diamond ◽

Sudden Change ◽

Growth Conditions ◽

Diamond Growth ◽

Major Constituent ◽

Natural Diamonds ◽

Type Ia ◽

Platelet Defects

Interest in the defects and impurities in natural diamond, which are found in even the most perfect stone, is driven by the fact that diamond growth occurs at a depth of over 120Km. They display characteristics associated with their origin and their journey through the mantle to the surface of the Earth. An optical classification scheme for diamond exists based largely on the presence and segregation of nitrogen. For example type Ia, which includes 98% of all natural diamonds, contain nitrogen aggregated into small non-paramagnetic clusters and usually contain sub-micrometre platelet defects on {100} planes. Numerous transmission electron microscope (TEM) studies of these platelets and associated features have been made e.g. . Some diamonds, however, contain imperfections and impurities that place them outside this main classification scheme. Two such types are described.First, coated-diamonds which possess gem quality cores enclosed by a rind that is rich in submicrometre sized mineral inclusions. The transition from core to coat is quite sharp indicating a sudden change in growth conditions, Figure 1. As part of a TEM study of the inclusions apatite has been identified as a major constituent of the impurity present in many inclusion cavities, Figure 2.

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Deposition of Boron-Doped Thin CVD Diamond Films from Methane-Triethyl Borate-Hydrogen Gas Mixture

Processes ◽

10.3390/pr8060666 ◽

2020 ◽

Vol 8 (6) ◽

pp. 666 ◽

Cited By ~ 2

Author(s):

Nikolay Ivanovich Polushin ◽

Alexander Ivanovich Laptev ◽

Boris Vladimirovich Spitsyn ◽

Alexander Evgenievich Alexenko ◽

Alexander Mihailovich Polyansky ◽

...

Keyword(s):

Film Growth ◽

Chemical Vapor ◽

Hydrogen Gas ◽

Diamond Growth ◽

Structural Defects ◽

Boron Doped Diamond ◽

Diamond Deposition ◽

Synthesis Conditions ◽

Surface Etching ◽

Boron Doped

Boron-doped diamond is a promising semiconductor material that can be used as a sensor and in power electronics. Currently, researchers have obtained thin boron-doped diamond layers due to low film growth rates (2–10 μm/h), with polycrystalline diamond growth on the front and edge planes of thicker crystals, inhomogeneous properties in the growing crystal’s volume, and the presence of different structural defects. One way to reduce structural imperfection is the specification of optimal synthesis conditions, as well as surface etching, to remove diamond polycrystals. Etching can be carried out using various gas compositions, but this operation is conducted with the interruption of the diamond deposition process; therefore, inhomogeneity in the diamond structure appears. The solution to this problem is etching in the process of diamond deposition. To realize this in the present work, we used triethyl borate as a boron-containing substance in the process of boron-doped diamond chemical vapor deposition. Due to the oxygen atoms in the triethyl borate molecule, it became possible to carry out an experiment on simultaneous boron-doped diamond deposition and growing surface etching without the requirement of process interruption for other operations. As a result of the experiments, we obtain highly boron-doped monocrystalline diamond layers with a thickness of about 8 μm and a boron content of 2.9%. Defects in the form of diamond polycrystals were not detected on the surface and around the periphery of the plate.

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Unusual Dependence of the Diamond Growth Rate on the Methane Concentration in the Hot Filament Chemical Vapor Deposition Process

Materials ◽

10.3390/ma14020426 ◽

2021 ◽

Vol 14 (2) ◽

pp. 426

Author(s):

Byeong-Kwan Song ◽

Hwan-Young Kim ◽

Kun-Su Kim ◽

Jeong-Woo Yang ◽

Nong-Moon Hwang

Keyword(s):

Growth Rate ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Methane Concentration ◽

Chemical Vapor ◽

Diamond Growth ◽

Lower Growth ◽

Filament Temperature ◽

Diamond Phase ◽

Hot Filament

Although the growth rate of diamond increased with increasing methane concentration at the filament temperature of 2100 °C during a hot filament chemical vapor deposition (HFCVD), it decreased with increasing methane concentration from 1% CH4 –99% H2 to 3% CH4 –97% H2 at 1900 °C. We investigated this unusual dependence of the growth rate on the methane concentration, which might give insight into the growth mechanism of a diamond. One possibility would be that the high methane concentration increases the non-diamond phase, which is then etched faster by atomic hydrogen, resulting in a decrease in the growth rate with increasing methane concentration. At 3% CH4 –97% H2, the graphite was coated on the hot filament both at 1900 °C and 2100 °C. The graphite coating on the filament decreased the number of electrons emitted from the hot filament. The electron emission at 3% CH4 –97% H2 was 13 times less than that at 1% CH4 –99% H2 at the filament temperature of 1900 °C. The lower number of electrons at 3% CH4 –97% H2 was attributed to the formation of the non-diamond phase, which etched faster than diamond, resulting in a lower growth rate.

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Optical Constant and Conformality Analysis of SiO2 Thin Films Deposited on Linear Array Microstructure Substrate by PECVD

Coatings ◽

10.3390/coatings11050510 ◽

2021 ◽

Vol 11 (5) ◽

pp. 510

Author(s):

Yongqiang Pan ◽

Huan Liu ◽

Zhuoman Wang ◽

Jinmei Jia ◽

Jijie Zhao

Keyword(s):

Thin Films ◽

Film Thickness ◽

Deposition Rate ◽

Optical Constant ◽

Photoelectron Spectroscopy ◽

Linear Array ◽

Chemical Vapor ◽

Rf Plasma ◽

X Ray ◽

Sio2 Thin Film

SiO2 thin films are deposited by radio frequency (RF) plasma-enhanced chemical vapor deposition (PECVD) technique using SiH4 and N2O as precursor gases. The stoichiometry of SiO2 thin films is determined by the X-ray photoelectron spectroscopy (XPS), and the optical constant n and k are obtained by using variable angle spectroscopic ellipsometer (VASE) in the spectral range 380–1600 nm. The refractive index and extinction coefficient of the deposited SiO2 thin films at 500 nm are 1.464 and 0.0069, respectively. The deposition rate of SiO2 thin films is controlled by changing the reaction pressure. The effects of deposition rate, film thickness, and microstructure size on the conformality of SiO2 thin films are studied. The conformality of SiO2 thin films increases from 0.68 to 0.91, with the increase of deposition rate of the SiO2 thin film from 20.84 to 41.92 nm/min. The conformality of SiO2 thin films decreases with the increase of film thickness, and the higher the step height, the smaller the conformality of SiO2 thin films.

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Nanofabrication using home-made RF plasma coupled chemical vapour deposition system

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194514603421 ◽

2014 ◽

Vol 32 ◽

pp. 1460342

Author(s):

Si Ci Ong ◽

Usman Ilyas ◽

Rajdeep Singh Rawat

Keyword(s):

Chemical Vapour ◽

Chemical Vapor ◽

Wide Band ◽

Zno Nanowires ◽

Operating Conditions ◽

Rf Plasma ◽

Zno Nanostructures ◽

Energetic Ions ◽

Cvd Method ◽

Etching Effect

Zinc oxide, ZnO , a popular semiconductor material with a wide band gap (3.37 eV) and high binding energy of the exciton (60 meV), has numerous applications such as in optoelectronics, chemical/biological sensors, and drug delivery. This project aims to (i) optimize the operating conditions for growth of ZnO nanostructures using the chemical vapor deposition (CVD) method, and (ii) investigate the effects of coupling radiofrequency (RF) plasma to the CVD method on the quality of ZnO nanostructures. First, ZnO nanowires were synthesized using a home-made reaction setup on gold-coated and non-coated Si (100) substrates at 950 °C. XRD, SEM, EDX, and PL measurements were used for characterizations and it was found that a deposition duration of 10 minutes produced the most well-defined ZnO nanowires. SEM analysis revealed that the nanowires had diameters ranging from 30-100 mm and lengths ranging from 1-4 µm. In addition, PL analysis showed strong UV emission at 380 nm, making it suitable for UV lasing. Next, RF plasma was introduced for 30 minutes. Both remote and in situ RF plasma produced less satisfactory ZnO nanostructures with poorer crystalline structure, surface morphology, and optical properties due to etching effect of energetic ions produced from plasma. However, a reduction in plasma discharge duration to 10 minutes produced thicker and shorter ZnO nanostructures. Based on experimentation conducted, it is insufficient to conclude that RF plasma cannot aid in producing well-defined ZnO nanostructures. It can be deduced that the etching effect of energetic ions outweighed the increased oxygen radical production in RF plasma nanofabrication.

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