Download i Digital PECVD Machine Construction ECE4007 Senior Design

Figure 4.2. Back plate used to mount PLC and terminal boards.
Plasma Generation & Film Deposition
There will be four gases available to generate the plasma: O2, Ar, CHF3 and C4F8. A
predefined recipe, given by the MiRC staff, will determine how much of each gas is required for
the process. MFCs will inject the gas into the chamber through throttling valves, that will
manage gas ratios in the chamber. These controllers interface with the PLC to keep track of the
amount of gas which has been injected. An RF Power supply and a matching network are
required to generate a high enough current to ignite and maintain the plasma. The Advanced
Turner ADX Generator was chosen because it contains the Power Supply as well as the
Matching Network with the controller. Generation of plasma is only possible when the gas has
been excited to a level similar to 600 watts of power passing through a 50 ohm load.
Plasma Project (ECE4007L01)
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