Microwave plasma chemical vapor deposition (MPCVD) has no internal electrode in the resonant cavity, which can avoid the pollution caused by electrode discharge. Its operating pressure range is relatively wide, the generated plasma has high density, large area, high stability, and does not contact with the vacuum vessel wall, so as to avoid the pollution of the vessel wall to the film...
Microwave plasma chemical vapor deposition (MPCVD) has no internal electrode in its resonator, which can avoid the pollution caused by electrode discharge. Its operating pressure range is relatively wide, the generated plasma has high density, large area, high stability, and does not contact with the vacuum vessel wall, thus avoiding the pollution of the vessel wall to the film. Therefore, microwave plasma chemical vapor deposition (MPCVD) has become one of the most promising diamond thin film deposition methods.
In the past, people used to use familiar magnetron power source to apply in MPCVD system. With the rapiddevelopment of technology, it has become a new trend to replace magnetron with solid RF microwave power source in MPCVD system.
Application of solid-state microwave generator in MPCVD system (take 6kW for example)
Advantage analysis of application of solid-state microwave source in MPCVD system.
In MPCVD device, microwave frequency, size of cavity, sample base and other factors will lead to the distribution of electric field, plasma state and distribution in the cavity. The following is the data analysis of a bachelor from Taiyuan University of Technology:
(Picture 1)
In MPCVD devices, even a frequency change of 10MHz will cause a strong change in the electric field, plasma intensity and distribution in the cavity
(Picture 2)
In MPCVD devices, the size of the resonator causes strong changes in the electric field, plasma intensity and distribution in the cavity
(Picture 3)
In the MPCVD device, the position of the sample base causes a strong change in the electric field, plasma intensity and distribution in the cavity
we can adjust the frequency and phase of the microwave source to make up for the changes of the electric field and plasma state distribution caused by the changes of the cavity size and sample base position .
MPCVD device with wattsine solid-state power generator will not change the working state of the device due to the replacement of power source, so it is necessary to re-adjust and set the working parameters of the device.
