Chemical Vapor Deposition
- Chemical vapor deposition equipment: common ones are microwave plasma chemical vapor deposition (MPCVD) equipment and hot filament chemical vapor deposition (HFCVD) equipment. Take MPCVD equipment as an example, it mainly consists of microwave generator, microwave transmission system, reaction chamber, gas supply system and so on. The microwave generator generates high power microwaves, which are introduced into the reaction chamber through the microwave transmission system, forming plasma in the reaction chamber, so that the carbon source gas (such as methane, hydrogen, etc.) is decomposed and deposited on the substrate to form diamond.
- Vacuum system:
It is used to pump the reaction chamber to a high vacuum state in order to exclude impurities such as air and provide a pure environment for the growth of diamond. Usually consists of mechanical pumps, molecular pumps, etc., which can reduce the pressure in the reaction chamber to 10-³ - 10-⁵Pa or even lower.
- Substrate Heating System:
During the CVD process, the substrate needs to be heated to promote the adsorption, decomposition and deposition of carbon source gases on the substrate surface. There are various types of substrate heating methods, such as resistance heating, radio frequency induction heating, etc. The heating temperature is generally between several hundred degrees Celsius and more than one thousand degrees Celsius.
- Gas supply and flow control system:
Precisely control the flow and proportion of carbon source gas, hydrogen and other auxiliary gases to meet the needs of diamond growth. The gas supply system usually includes gas cylinders, pressure reducing valves, mass flow meters, etc. Through the flow control system, the flow rate of various gases can be precisely adjusted according to the set parameters.
