Code of Federal Regulations > Title 40 > Chapter I > Part 98 > Subpart I > Appendix - Table I-5 to Subpart I of Part 98—Default Emission Factors (1-Uij) for Gas Utilization Rates (Uij) and By-Product Formation Rates (Bijk) for MEMS Manufacturing

Regulations last checked for updates: Nov 25, 2024

Title 40 - Protection of Environment last revised: Nov 21, 2024

Appendix - Table I-5 to Subpart I of Part 98—Default Emission Factors (1-Uij) for Gas Utilization Rates (Uij) and By-Product Formation Rates (Bijk) for MEMS Manufacturing

Process type factors	Process gas i
Process type factors	CF4	C2F6	CHF3	CH2F2	C3F8	c− C4F8	NF3 Remote	NF3	SF6	C4F6a	C5F8a	C4F8Oa
Etch 1-Ui	0.7	¹0.4	¹0.4	¹0.06	NA	¹0.2	NA	0.2	0.2	0.1	0.2	NA
Etch BCF4	NA	¹0.4	¹0.07	¹0.08	NA	0.2	NA	NA	NA	¹0.3	0.2	NA
Etch BC2F6	NA	NA	NA	NA	NA	0.2	NA	NA	NA	¹0.2	0.2	NA
CVD Chamber Cleaning 1-Ui	0.9	0.6	NA	NA	0.4	0.1	0.02	0.2	NA	NA	0.1	0.1
CVD Chamber Cleaning BCF4	NA	0.1	NA	NA	0.1	0.1	²0.02	²0.1	NA	NA	0.1	0.1
CVD Chamber Cleaning BC3F8	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	0.4

Notes: NA = Not applicable; i.e., there are no applicable default emission factor measurements for this gas. This does not necessarily imply that a particular gas is not used in or emitted from a particular process sub-type or process type.

¹ Estimate includes multi-gas etch processes.

² Estimate reflects presence of low-k, carbide and multi-gas etch processes that may contain a C-containing fluorinated GHG additive.

[75 FR 74818, Dec. 1, 2010, as amended at 78 FR 68225, Nov. 13, 2013]

authority: 42 U.S.C. 7401-7671q.

source: 74 FR 56374, Oct. 30, 2009, unless otherwise noted.