Process and device for diamond synthesis by CVD

A chemical vapour deposition chamber defining a volume and having an inlet adapted to enable a gas or a plasma or both a gas and a plasma to enter the chamber, and an outlet adapted to depressurize the chamber, the chamber further comprising:

• at least one anode;
• a substrate forming a cathode;
• a hybrid power supply in a circuit with the anode and cathode, the hybrid power supply comprising a direct current (DC) to the anode and cathode and the hybrid power supply comprising a source of current by radiofrequencies enabled to operate in an alternating (RF) current;
• and
• a cylinder-shaped grille comprising at least one ring or tube of refractory material which increases the volume density of activated atoms near the substrate and therefore the deposition speed of the material to be synthesised and is further suitable for homogenizing the plasma around the substrate.

A method of chemical vapour deposition comprising:

• providing a vapour deposition chamber defining a volume and having an inlet and an outlet wherein the chamber further comprises at least one anode, a substrate forming a cathode, a hybrid power supply in a circuit with the anode and cathode, the hybrid power supply comprising a direct current (DC) to the anode and cathode and the hybrid power supply comprising a source of current by radiofrequencies enabled to operate in an alternating (RF) current;
• providing a negative pressure to the chamber;
• introducing a carrier gas containing carbon atoms into the chamber;
• and
• creating a plasma near the substrate to generate reactive carbon atoms, wherein
• the plasma is created by applying a direct current and a radio-frequency alternating current between the cathode and the anode;
• and
• providing the chamber with at least one magnet being adapted to apply a linear magnetic field within the chamber;
• and
• applying the linear magnetic field near the substrate.

A method for synthesising an allotropic form of carbon material in a chemical vapour deposition chamber and on a synthesis substrate, between two plasma-generating electrodes, according to which the method comprising:

• providing a vapour deposition chamber defining a volume and having an inlet and an outlet wherein the chamber further comprises at least one anode, a substrate forming a cathode, a hybrid power supply in a circuit with the anode and cathode, the hybrid power supply comprising a source of direct current (DC) to the anode and cathode and the hybrid power supply comprising a source of current by radiofrequencies enabled to operate in an alternating (RF) current;
• introducing a carrier gas containing atoms of the material to be synthesised into the chamber, and
• generating a plasma near the substrate to activate the atoms of the carrier gas containing atoms of the material to be synthesised,
• compressing plasma by providing cylinder-shaped grille comprising at least one ring or tube of refractory material which increases the volume density of activated atoms near the substrate and therefore the deposition speed of the material to be synthesised and is further suitable for homogenizing the plasma around the substrate.