Gas-jet synthesis of diamond coatings on silicon substrates from an H$_2$ + CH$_4$ + Ar mixture activated in a microwave discharge

The paper described further development of a gas-jet method of synthesizing diamond coatings with the use of a high-velocity jet for transporting the gas mixture (hydrogen, methane, and argon) activated in a microwave discharge to a silicon substrate. A substrate holder is developed, which ensures substrate integrity under thermal loading under conditions of chemical vapor deposition. The diamond synthesis rate in the present experiments is higher than that obtained previously in microwave plasma-assisted chemical vapor deposition experiments without addition of argon.