Make plasma (dry) etcher.

Hello.

I am going to make plasma etcher cause of my pzt ceramic.
There is no way to pattering it so I decided to make plasma etcher.

Making plasma or plasma chamber is exist a lot at google or youtube.

Just making vaccum chamber and adding vaccum pump and power supply, it's done.

My question is why people do a HF(13MHz) not a DC generator at "plasma etcher"

At my mind, just hitting electron, doesn't it DC cause it's not a capacitor that have air.
I think it didn't have any insulator so doesn't it can deliver electrons?

Also I didn't understand WHY I need to supply GAS?(like Al203)

With AC you move the molecules backwards and forwards and cause them to collide. This knocks electrons out from the atom and ionises the gas.

You need gas to be ionised so that it forms a plasma in the first place. Plasma is a state of matter with a vacuums you have no matter available to make a plasma with.