Homoepitaxial growth of CVD diamond: effect of nitrogen contaminations on growth rates

1995 ◽  
Vol 416 ◽  
Author(s):  
C. Wild ◽  
R. Locher ◽  
P. Koidl
Keyword(s):  
Growth Rate ◽  
Microwave Plasma ◽  
Diamond Films ◽  
Polycrystalline Diamond ◽  
Laser Interferometry ◽  
Perfect Agreement ◽  
Homoepitaxial Growth ◽  
Process Gas ◽  
A Minor

ABSTRACTHomoepitaxial diamond films were deposited on {100} and {111} oriented substrates using microwave plasma assisted CVD. The growth rate was measured in situ using laser interferometry. Various amounts of 15N2 were admixed to the process gas (0-50 ppm). The growth rate on {100} faces was found to increase significantly (by a factor 1.8) with increasing 15N2 content. In contrast, on { 111 } faces only a minor increase of the growth rate upon nitrogen admixture was observed. These findings are in perfect agreement with the observed influence of nitrogen contaminations on the α-parameter, as derived by the X-ray texture analysis of polycrystalline diamond films [1]

Polycrystalline Diamond Film Resistors

1992 ◽  
Vol 242 ◽  
Author(s):  
L. M. Edwards ◽  
J. L. Davidson
Keyword(s):  
Diamond Film ◽  
Microwave Plasma ◽  
Diamond Films ◽  
Polycrystalline Diamond ◽  
Plasma Cvd ◽  
Microwave Plasma Cvd ◽  
P Type ◽  
Polycrystalline Diamond Film ◽  
Effective Source

ABSTRACTThe technology to fabricate polycrystalline diamond film resistors has been initiated using modified thick film patterning techniques and in situ solid source doping.Doping of polycrystalline diamond films in microwave plasma CVD systems has been achieved historically through use of diborane gas, which may contaminate the deposition system causing all diamond films thereafter to be doped p-type. We have attempted noncontaminating in situ doping utilizing two solid source dopants, and have met with preliminary success.The more effective source (B2O3) produces a fairly even dopant concentration across the substrate, with sheet resistances ranging from 800 ohms per square to 4500 ohms per square. The other source (BN) showed significant doping in a narrow band surrounding the source, but the doping concentration decreased rapidly with distance from the source. Films grown afterwards with no doping were evaluated through resistance measurements; no evidence of doping contamination was observed.

Novel in situ production of smooth diamond films

1998 ◽  
Vol 13 (7) ◽  
pp. 1735-1737 ◽  
Author(s):  
Donald R. Gilbert ◽  
Dong-Gu Lee ◽  
Rajiv K. Singh
Keyword(s):  
Electron Cyclotron Resonance ◽  
Microwave Plasma ◽  
Ion Beam ◽  
Diamond Films ◽  
Extraction Process ◽  
Pure Oxygen ◽  
Average Roughness ◽  
Process System ◽  
Unique Method

We have developed a unique method to produce smooth diamond films using a modified microwave plasma process system. This method consists of sequential in situ deposition and planarization in an electron cyclotron resonance plasma system. Diamond films were deposited to a thickness of 3.0 μm in this system at a pressure of 1.000 Torr from gas mixtures of methanol and hydrogen. Deposition was followed by planarization using a two-grid ion beam extraction process with a pure oxygen plasma at 10 mTorr. The average roughness of the diamond films so produced was as low as 30 nm, which was a factor of two lower than that of the as-deposited diamond films.

Determination of diamond [100] and [111] growth rate and formation of highly oriented diamond film by microwave plasma-assisted chemical vapor deposition

1995 ◽  
Vol 10 (12) ◽  
pp. 3115-3123 ◽  
Author(s):  
Hideaki Maeda ◽  
Kyo Ohtsubo ◽  
Miki Irie ◽  
Nobutaka Ohya ◽  
Katsuki Kusakabe ◽  
...  
Keyword(s):  
Growth Rate ◽  
Chemical Vapor Deposition ◽  
Relative Growth Rate ◽  
Diamond Film ◽  
Vapor Deposition ◽  
Microwave Plasma ◽  
Chemical Vapor ◽  
Relative Growth ◽  
Homoepitaxial Growth ◽  
Novel Method

A novel method was proposed for measuring the epitaxial growth rate of diamond by microwave plasma-assisted chemical vapor deposition (MPCVD). Cubo-octahedral crystals were formed on an Si(100) wafer and were used as the substrate in the homoepitaxial growth. Growth rates of the {100} and {111} were simultaneously measured from the change in the top view size of crystals. Thus, the relative growth rate of {100} to {111} was obtained without any limitation of its value. The homoepitaxial growth rate was strongly affected by the type of diamond faces, CH4 concentration in the gas phase, and deposition temperature. The growth rate of {100} was more dependent on CH4 concentration than that of {111}, while the activation energy for the [100] growth was about half that for the [111] growth. These tendencies were in accord with growth mechanisms proposed for each diamond plane. Reaction conditions were optimized based on the relative growth rate of (100) to (111) planes, and a highly oriented (100) diamond film with a quite smooth surface was formed on an Si(100) wafer.

Morphology of Diamond Films Grown by DC Plasma Jet CVD

1989 ◽  
Vol 162 ◽  
Author(s):  
Kazuaki Kurihara ◽  
Ken-Ichi Sasaki ◽  
Motonobu Kawarada ◽  
Nagaaki Koshino
Keyword(s):  
Growth Rate ◽  
Microwave Plasma ◽  
Diamond Films ◽  
High Growth ◽  
Plasma Jet ◽  
High Growth Rate ◽  
Plasma Cvd ◽  
Dc Plasma ◽  
Synthesis Conditions ◽  
Microwave Plasma Cvd

ABSTRACTIt is well known that diamond films synthesized from the gas phase have well defined crystal habits which are affected strongly by synthesis conditions. Though there have been many studies of the morphologies of diamond films synthesized by microwave plasma CVD [1,2,3], there have been relatively few reports on the morphologies of these films grown using new high growth rate techniques such as DC plasma jet CVD [4]. Morphology control is very important to keep flat surface, when producing thick diamond films by high growth rate techniques. In this paper we report our investigation of the morphology and growth of diamond films synthesized by DC plasma jet CVD.

scholarly journals SOME ASPECTS OF THE CULTURE OF EUCHEMA

1970 ◽  
Vol 17 ◽  
pp. 145-146
Author(s):  
U. Horstman ◽  
A. Colina ◽  
W. Schramm
Keyword(s):  
Growth Rate ◽  
The Philippines ◽  
Minor Role ◽  
Bacterial Disease ◽  
Surrounding Water ◽  
Low Salinity ◽  
In Situ Experiments ◽  
Spraying Plants ◽  
A Minor

Eucheuma striatum and Eucheuma spinosum, are red algae of commercial value because of their carrageenin content, to an increasing extent are cultivated in the Philippines. The influence of environmental factors on growth rate and photosynthesis of these seaweeds were studied through observations in their natural biotope in seaweed farms, from in-situ experiments, and photosynthesis experiments in an incubator. While difference in light intensity and temperature play only a minor role, the algae were found out to be sensitive to low salinity and to the amount of dissolved gases and nutrients in the surrounding seawater. The algae can only be cultured in areas where there is sufficient current but to a cer-tain extent lack of current can be compensated by exposing the plants to wave action. This leads to certain conclusions regarding the most suitable method of commercial Eucheuma culture. Eucheuma can be successfully cultured in small rafts or in floating baskets in areas where there is insufficient current for the use of fixed nets or strings. There is evidence that-the CO2 -02 metabolism in the surrounding water plays an important role in Eucheuma growth. Eucheuma harvest can be further increased by introducing more nutrients. Fertilizing with phosphate caused a bigger increase in growth rate than with nitrogen. The method of spraying plants after temporarily removing them from the water, found to be more effective than fertilizing solutions by the use of clay pots. The presence of a bacterial disease, locally referred to as "ice-ice", was recognized as a clear indication that certain environment conditions were unfavourable for Eucheuma culture. Low salinity, in the first place, but also lack of current favors the attack of "ice-ice". Finally, it was found that Eucheuma adapts itself to its culture site in such a way that after maintaining seedlings in an area for a sufficient length of time, the cultured plants showed better growth rates and were resistent to unfavorable conditions than plants recently transferred to the area.

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