Nik,
Can you explain why higher substrate power and shorter cycles could
reduce the scallops?
What chemistries have been used in Bosch process? Is it a pure chemical
etch or a combination of chemical + physical etch with high energetic
bombardment of ions using high substrate power?

Thanks,
Chan

----- Original Message -----
*From:* Nicolas Duarte 
*To:* General MEMS discussion 
*Sent:* 09 September 2006 16:30:13
*Subject:* [mems-talk] DRIE etching


> This is what DRIE does.  If you are using the Bosch process there is
> no way to completely get rid of the scallops, but you can reduce them
> by optimizing your process.  Higher substrate power and shorter cycles
> should help out.
>
> If you want to completely get rid of scallops I am told that the Cryo
> process is a DRIE process that has no scallops (since there is no
> cycling in that) but you need a special tool to do it (most DRIE
> machines cannot switch between the two processes).