HFC/IFC HDP Etch Study(Jun. 1997 - Aug. 1997)
Goal: screen several new chemistries in a dielectric etch application (high aspect ratio TEOS via etch); characterize process performance and emissions
Process tool: inductively coupled high density plasma etch tool
Chemistries examined:
- 2H-heptafluoropropane (CF3-CFH-CF3) - TSCA inventory status: not listed
- Iodotrifluoromethane (CF3I) - TSCA inventory status: listed
- 2-iodoheptafluoropropane (CF3-CFI-CF3) - TSCA inventory status: listed
- 1-iodoheptafluoropropane (CF2I-CF2-CF3) - TSCA inventory status: listed
Significant results:
- Substantial global warming emissions reductions possible
- Three chemistries proved viable from a process standpoint. 0.6, 0.45, 0.35 ?m (nominal printed CD) features were successfully etched:
- 2H-heptafluoropropane - unoptimized processes showed etch capability equivalent to C3F8 process with ~60% emissions savings
- 1- and 2-iodoheptafluoropropane - unoptimized processes showed very high etch rates (over 10,000 Å/min) with emissions savings in 80-90% range