Code of Federal Regulations > Title 40 > Chapter I > Part 98 > Subpart I > Appendix - Table I-3 to Subpart I of Part 98—Default Emission Factors (1-Uij) for Gas Utilization Rates (Uij) and By-Product Formation Rates (Bijk) for Semiconductor Manufacturing for 150 mm and 200 mm Wafer Sizes

Regulations last checked for updates: Feb 21, 2025

Title 40 - Protection of Environment last revised: Nov 21, 2025

Appendix - Table I-3 to Subpart I of Part 98—Default Emission Factors (1-Uij) for Gas Utilization Rates (Uij) and By-Product Formation Rates (Bijk) for Semiconductor Manufacturing for 150 mm and 200 mm Wafer Sizes

Table I-3 to Subpart I of Part 98—Default Emission Factors (1-Uij) for Gas Utilization Rates (Uij) and By-Product Formation Rates (Bijk) for Semiconductor Manufacturing for 150 mm and 200 mm Wafer Sizes

Process type/sub-type	Process gas i
Process type/sub-type	CF4	C2F6	CHF3	CH2F2	C2HF5	CH3F	C3F8	C4F8	NF3	SF6	C4F6	C5F8	C4F8O
Etching/Wafer Cleaning
1-Ui	0.73	0.72	0.51	0.13	0.064	0.70	NA	0.14	0.19	0.55	0.083	0.072	NA
BCF4	NA	0.10	0.085	0.079	0.077	NA	NA	0.11	0.0040	0.13	0.095	NA	NA
BC2F6	0.041	NA	0.035	0.025	0.024	0.0034	NA	0.037	0.025	0.11	0.073	0.014	NA
BC4F8	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA
BC3F8	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA
BCHF3	0.091	0.047	NA	0.049	NA	NA	NA	0.040	NA	0.0012	0.066	0.0039	NA
Chamber Cleaning
In situ plasma cleaning
1-Ui	0.92	0.55	NA	NA	NA	NA	0.40	0.10	0.18	NA	NA	NA	0.14
BCF4	NA	0.19	NA	NA	NA	NA	0.20	0.11	0.14	NA	NA	NA	0.13
BC2F6	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	0.045
BC3F8	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA
Remote plasma cleaning
1-Ui	NA	NA	NA	NA	NA	NA	NA	NA	0.028	NA	NA	NA	NA
BCF4	NA	NA	NA	NA	NA	NA	NA	NA	0.015	NA	NA	NA	NA
BC2F6	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA
BC3F8	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA
BF2	NA	NA	NA	NA	NA	NA	NA	NA	0.5	NA	NA	NA	NA
In situ thermal cleaning
1-Ui	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA
BCF4	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA
BC2F6	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA
BC3F8	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA

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.

[89 FR 31920, Apr. 25, 2024]

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

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