Step 44. Backside etch

Step	Process	Date	Operator
44.1	Remove PR in O2 plasma in Matrix 2.5 min ashing Clean wafers in Sink8 piranha. No HF dip. Dehydrate wafers in oven @ 120C for 30 min. Coat wafers on SVGCOAT6 Dip off native oxide on poly in sink8 5/1 BHF. Etch Poly-Si from backside in Lam5. Recipe 5003 w/o overetch. Etch to endpoint plus ~10sec. Final dip into 5/1 HF in sink8 until dewet (~1min). Include NCH, PCH, Tpoly1,2 to etch native oxide (~20 sec) Remove PR in O2 plasma in Matrix 2.5 min ashing Clean wafers in Sink8	11/07/07	Pongracz