EFFECT OF THE GAS MIXTURE FLOW RATE ON THE PROCESS OF DIAMOND SYNTHESIS FROM A HIGH-VELOCITY MICROWAVE PLASMA

Spatially resolved gain measurements at 10.6 μm have been made transverse to the discharge in an axially flowing CO2 laser amplifier. The composition of the amplifier medium has been varied to include initially pure CO2, binary mixtures of CO2:CO, CO2:He, and CO2:N2, and triple mixtures of CO2:N2:He. Strong spatial variations of gain are observed which depend on the gas mixture, flow rate, temperature, pressure, and current. Corresponding spatial intensity profiles of the sidelight emission of CO2 at 4.3 μm are shown.

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GAS-PHASE SYNTHESIS OF DIAMOND STRUCTURES

NONEQUILIBRIUM PROCESSES. Vol. 2. Fundamentals of combustion ◽

10.30826/nepcap2018-2-01 ◽

2020 ◽

Author(s):

A. K. Rebrov ◽

Keyword(s):

Gas Phase ◽

Building Material ◽

Microwave Plasma ◽

Diamond Surface ◽

Gas Mixture ◽

Diamond Synthesis ◽

Phase Synthesis ◽

Transfer Processes ◽

Carbon Structures ◽

Complex Influence

The diamond synthesis from vapor (gas) phase is realized under complex influence of nonequilibrium transfer processes in activated gas mixtures by formation of carbon structures on a nascent diamond surface. The microwave plasma generates an active gas mixture and fragments of building material are transported

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Structural and surface analysis of chemical vapor deposited boron doped aluminum nitride thin film on aluminum substrates

Materials Science-Poland ◽

10.2478/msp-2019-0056 ◽

2019 ◽

Vol 37 (3) ◽

pp. 395-403 ◽

Cited By ~ 1

Author(s):

Shanmugan Subramani ◽

Mutharasu Devarajan

Keyword(s):

Thin Film ◽

Thin Films ◽

Aluminum Nitride ◽

Flow Rate ◽

Chemical Vapor ◽

Film Deposition ◽

Gas Mixture ◽

Mixture Flow ◽

Mixture Ratio ◽

Aluminum Substrates

AbstractChemical vapor deposition (CVD) process was conducted for synthesis of boron (B) doped aluminum nitride (B-AlN) thin films on aluminum (Al) substrates. To prevent melting of the Al substrates, film deposition was carried out at 500 °C using tert-buthylamine (tBuNH2) solution delivered through a bubbler as a nitrogen source instead of ammonia gas (NH3). B-AlN thin films were prepared from three precursors at changing process parameters (gas mixture ratio). X-ray diffraction (XRD) technique and atomic force microscope (AFM) were used to investigate the structural and surface properties of B-AlN thin films on Al substrates. The prepared thin films were polycrystalline and composed of mixed phases {cubic (1 1 1) and hexagonal (1 0 0)} of AlN and BN with different orientations. Intensive AlN peak of high intensity was observed for the film deposited at a flow rate of the total gas mixture of 25 sccm. As the total gas mixture flow decreased from 60 sccm to 25 sccm, the crystallite size of AlN phase increased and the dislocation density decreased. Reduced surface roughness (10.4 nm) was detected by AFM for B-AlN thin film deposited on Al substrate using the lowest flow rate (25 sccm) of the total gas mixture.

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