Maybe that is due to the deposition of the etching byproduct, my advice is to
clean your chamber.


ÔÚÄúµÄÀ´ÐÅÖÐÔø¾­Ìáµ½:
>From: [email protected]
>Reply-To: General MEMS discussion 
>To: [email protected]
>Subject: [mems-talk] what is the problem with our STS ICP?
>Date:Thu, 18 Sep 2008 21:22:55 -0400 (EDT)
>
>Hi, We have a STS ICP, working fine until recently.
>
> Problem is when using pure gas, such as O2 or CF4 alone, then plasma is
> stable. However if using mixed gas, O2+CF4, then plasma unstable. Lower
> top coil power helps but etch rate would be much slower compare to before.
>
> Can someone give a suggestion? Thanks.