The most important subject in discussing CVD, are the chemical reactions that take place in the reactor.

One of the goal of this module is to learn the differences between different types of CVD and also how to influence the properties (composition, density) of the deposited films by changing the deposition paramaters (pressure, power, concentration of gases)

REACTOR

                               

This is a cluster system with two CVD chambers connected to a loader. As you can see, the vacuum is not broken between the two deposition processes. Tubes enter the reaction chamber, introducing and removing the gases.

 

MAIN STEPS IN A REACTOR can be seen in the animation below:

• gas introduced
• wafer and gas heated
• reactions take place at the wafer or in the gas
• pressure maintained constant by pumping out the gas and by-products