Effective cooling of substrates with low thermal conductivity under conditions of gas-jet MPCVD diamond synthesis

The paper presents the results of an experimental study of heating molybdenum and silicon substrates under the conditions of gas-jet deposition of diamond structures using the precursor gases of a microwave discharge to activate. A cooled substrate holder using a metal melt to improve heat removal by reducing the thermal resistance between the substrate and the substrate holder has been developed. The use of the melt allowed lowering the temperature of the silicon substrate under the conditions of gas-jet deposition to a level that ensures the preservation of its structure. The developed substrate holders were used to carry out gas-jet synthesis of diamond structures on molybdenum and silicon substrates.

Влияние науглероживания вольфрама на активацию газа при синтезе алмазных структур

In order to develop a gas-jet method of diamond structures deposition, the flow of hydrogen and methane mixture through heated tungsten coaxial cylindrical channels with a built-in tungsten spiral is studied. The main attention is paid to the study of the carburization of tungsten surfaces during gas-jet deposition and the effect of carburization on the deposition rate and the morphology of the deposited coatings. A series of experiments to study the carburization of tungsten surfaces under different conditions for feeding a mixture of hydrogen and methane is performed. The flow parameters are investigated by the direct simulation Monte Carlo method. The possible ways of delivering methane and its fragments onto the surface of the spiral are determined.