That is determined by controlled input. Most CVD thin films are done in layers akin to a sandwich. The first layer is usually an adhesive layer to help bond the thin film to the wafer substrate. Then the subsequent layers will be deposited on to the adhesive layer. Example, TiN is a very common thin film. Between each layer, the reactor is often purged of the previous layer's contaminants before a new layer is applied. A purge can be usually done with H2 or N2 though H2 is generally recommended because it will not nitride at higher temperatures like N2. Some manufacturers of TiN will deposit TiCN as the adhesive layer and then deposit TiC as the central layer with TiN being the cover layer.
Great clear and concise presentation. Thank you
Best NPTEL discussion, I've ever come across!
I wonder why there is so much fight for the IITs. Simply wonderful
Great lecture sir. Can you suggest the process for Zinc selenide
Thank you
How do you know when one layer is filled and another one starts?
That is determined by controlled input. Most CVD thin films are done in layers akin to a sandwich. The first layer is usually an adhesive layer to help bond the thin film to the wafer substrate. Then the subsequent layers will be deposited on to the adhesive layer. Example, TiN is a very common thin film.
Between each layer, the reactor is often purged of the previous layer's contaminants before a new layer is applied. A purge can be usually done with H2 or N2 though H2 is generally recommended because it will not nitride at higher temperatures like N2.
Some manufacturers of TiN will deposit TiCN as the adhesive layer and then deposit TiC as the central layer with TiN being the cover layer.
Gostaria que o Sr ensinasse sobre um reator para fabricação de diamantes.