(3) Radio Frequency Plasma CVD (RFCVD)RF can be used to generate plasma by two different methods, the capacitive coupling method and the inductive coupling method.RF plasma CVD uses a frequency of 13.56 MHz.The advantage of RF plasma is that it diffuses over a much larger area than microwave plasma.However, the limitation of RF capacitively coupled plasma is that the frequency of the plasma is not optimal for sputtering, especially if the plasma contains argon.Capacitively coupled plasma is not suitable for growing high quality diamond films since ion bombardment from the plasma can lead to severe damage to the diamond. Polycrystalline diamond films have been grown using RF induced plasma under deposition conditions similar to microwave plasma CVD.Homogeneous epitaxial diamond films have also been obtained using RF-induced plasma-enhanced CVD.
(4) DC Plasma CVD
DC plasma is another method of activating a gas source (generally a mixture of H2, and hydrocarbon gas) for diamond film growth.DC plasma-assisted CVD has the ability to grow large areas of diamond films, and the size of the growth area is limited only by the size of the electrodes and the DC power supply.Another advantage of DC plasma-assisted CVD is the formation of a DC injection, and typical diamond films obtained by this system are deposited at a rate of 80 mm/h. In addition, since various DC arc methods can deposit high-quality diamond films on non-diamond substrates at high deposition rates, they provide a marketable method for the deposition of diamond films.
(5) Electron cyclotron resonance microwave plasma enhanced chemical vapor deposition (ECR-MPECVD)The DC plasma, RF plasma, and microwave plasma described earlier all dissociate and decompose H2, or hydrocarbons, into atomic hydrogen and carbon-hydrogen atom groups, thereby contributing to the formation of diamond thin films. Since electron cyclotron resonance plasma can produce high density plasma (>1x1011cm-3), ECR-MPECVD is more suitable for the growth and deposition of diamond films.However, due to the low gas pressure (10-4- to 10-2 Torr) used in the ECR process, which results in a low deposition rate of diamond films, the method is currently only suitable for the deposition of diamond films in the laboratory.
–This article is released by vacuum coating machine manufacturer Guangdong Zhenhua
Post time: Jun-19-2024