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PECVD technology technique

Plasma-enhanced chemical vapor deposition is a method in which gas is excited in chemical vapor deposition to generate low-temperature plasma to enhance the chemical activity of reactive species, thereby performing epitaxy. This method can form solid films at lower temperatures. For example, the matrix material is placed on the cathode in a reaction chamber, the reaction gas is introduced to a lower pressure (1-600Pa), the matrix is kept at a certain temperature, and a glow discharge is generated in a certain way, the gas near the surface of the matrix is ionized, and the reaction gas is obtained. activation, and at the same time cathode sputtering occurs on the surface of the substrate, thereby improving the surface activity. There are not only the usual thermochemical reactions on the surface, but also complex plasma chemical reactions. 

The deposited film is formed under the combined action of these two chemical reactions. 

The methods of exciting glow discharge mainly include: radio frequency excitation, DC high voltage excitation, pulse excitation and microwave excitation. 


The main advantages of plasma enhanced chemical vapor deposition are that the deposition temperature is low, and the impact on the structure and physical properties of the substrate is small; the film thickness and composition uniformity are good; the film structure is dense and pinholes are few; Wide range of metal films, inorganic films and organic films can be prepared.


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