I am surprised that this method works. Can you clarify? KOH attacks
pretty much every resist I've used. What is the function of the HF in
KOH? How do you prevent lateral seepage with Kapton mask? If it works,
then it would be a very simple method, but I am skeptical.



On Tue, Dec 7, 2010 at 1:10 AM, Nabhiraj Yalagoud
 wrote:
> hi,
>
> Another good way is to etch by HF.
> coat with PMMA / polymer/ scratch 1 mm diameter by scrubber and remove PMMA
> and etch it in HF / KOH
>
> Or put a kapton tape on the wafer by punching a 1 mm hole on the tape. and
> etch it. It may take more time but it is also a very cheap method.
> remember to tape backside also and shake it while etching.
>
> Nabhiraj