Step 40. Backside Etch

Step	Process	Date	Operator
40.1	Remove PR in O2 plasma in Matrix  Clean wafers in sink8 piranha (MEMS). No HF dip.  Dehydrate wafers in oven @ 120C for 30 min.	11/15/04	Horvath
40.2	a) Coat wafers on SVGCOAT6 b) Dip off native oxide on poly in sink8 5/1 BHF. Note: check step 34. (TEOS dep. only on front vs. furnce LTO on backside too) c) Etch Poly-Si in Lam5. Recipe 5003 w/o overetch. Etch to endpoint plus ~10sec. d) Final dip into 5/1 HF in sink8 until dewet (~1min). Include NCH, PCH, Tpoly1,2 to etch native oxide (~20 sec)	11/16/04	Horvath