[mems-talk] Reasons for Plasma Flickering in Oxford Plasmalab 80 Plus RIE system

[PRAMOD GUPTA]

Hi
   
  Does any one know what could be the reasons for Plasma Flickering in Oxford Plasmalab 80 Plus RIE system?. I am trying to etch polymers with SF6/O2/CHF3 gas chemistry at 30mTorr, 200W. The recipe was working perfect earlier. Pure O2 plasma, even at 30mTorr, does not flicker at all. It starts flickering when you mix O2 with SF6 and/or CHF3. What could be the reasons? I will appreciate your feedback.
   
  With regards,     


Pramod Gupta 
21084 Red Fir Court 
Cupertino, CA 95014 
Phone: (408) 253-1646