crazy idea: self made rf laminate - is it possible?

idea: take o.xx mm copper roll, 0.5mm teflon roll, press it, maybe put some adhesive. In successful case we get flexible pcb.
ok, i know, maybe it is stupid idea. many probles. But maybe someone thinked or did it?

I don't think you'll be able to control your impedance accurately. But if that's not a concern, go for it. You still have to figure out a way to cut/etch your copper. Your ARE aware that there are commercially available flexible pcbs, right?

Sure, except you need to copper tape to tightly stick to the teflon part....and you know that is going to be a problem!

If the Teflon is properly prepared, adhesives will bond to it quite well. Some people use mechanical roughing, like media blasting. My favorite way is to chemically etch the surface.

Commercial etchants for bonding Teflon are available for that purpose. Or, if you have access to metallic sodium, you can make your own. One formula dissolves the sodium in naphthalene with another co-solvent, such a diglyme. Obviously, you need to keep the reagents very dry and don't use anything with an easily removed proton, such and as an alcohol. Alternatively, you can dissolve the sodium in liquid ammonia. The former method requires less sophisticated equipment.

John

Edit: Here is a link to bondable Teflon sheets. Only one surface is etched, as most applications would want a slippery surface on the other side: http://www.mcmaster.com/#bondable-fi...ptfe-)/=gkrd3s

It might be easier to ask for a free sample of existing microwave substrates. The substrate manufacturers usually have small sheets as a sample.

Yeah, but those teflon etchants are very poisonous. I would not screw with them unless you really knew what you were doing!

Copper is quite poisonous too, but most of the people on this forum deal with it without problems. The fact is, the commercial etchant is no more poisonous than moth balls that anyone can buy at a store.

John