Except as provided in this section, all of the terms used in this subpart have the same meaning given in the Clean Air Act and subpart A of this part. If a conflict exists between a definition provided in this subpart and a definition provided in subpart A, the definition in this subpart takes precedence for the reporting requirements in this subpart.
Abatement system means a device or equipment that is designed to destroy or remove fluorinated GHGs or N2O in exhaust streams from one or more electronics manufacturing production processes, or for which the destruction or removal efficiency for a fluorinated GHG or N2O has been properly measured according to the procedures under Sec. 98.94(f)(4), even if that abatement system is not designed to destroy or remove fluorinated GHGs or N2O. The device or equipment is only an abatement system for the individual fluorinated GHGs or N2O that it is designed to destroy or remove or for the individual fluorinated GHGs or N2O for which destruction or removal efficiencies were properly measured according to the procedures under Sec. 98.94(f)(4).
Actual gas consumption means the quantity of gas used during wafer/substrate processing over some period based on a measured change in gas container weight or gas container pressure or on a measured volume of gas.
By-product formation means the creation of fluorinated GHGs during electronics manufacturing production processes or the creation of fluorinated GHGs by an abatement system. Where the procedures in Sec. 98.93(a) are used to calculate annual emissions, by-product formation is the ratio of the mass of the by-product formed to the mass flow of the input gas. Where the procedures in Sec. 98.93(i) are used to calculate annual emissions, by-product formation is the ratio of the mass of the by-product formed to the total mass flow of all fluorinated GHG input gases.
Chamber cleaning is a process type that consists of the process sub-types defined in paragraphs (1) through (3) of this definition.
(1) In situ plasma process sub-type consists of the cleaning of thin-film production chambers, after processing substrates, with a fluorinated GHG cleaning reagent that is dissociated into its cleaning constituents by a plasma generated inside the chamber where the film is produced.
(2) Remote plasma process sub-type consists of the cleaning of thin-film production chambers, after processing substrates, with a fluorinated GHG cleaning reagent dissociated by a remotely located plasma source.
(3) In situ thermal process sub-type consists of the cleaning of thin-film production chambers, after processing substrates, with a fluorinated GHG cleaning reagent that is thermally dissociated into its cleaning constituents inside the chamber where thin films are produced.
Controlled emissions means the quantity of emissions that are released to the atmosphere after application of an emission control device (e.g., abatement system).
Destruction or removal efficiency (DRE) means the efficiency of an abatement system to destroy or remove fluorinated GHGs, N2O, or both. The destruction or removal efficiency is equal to one minus the ratio of the mass of all relevant GHGs exiting the abatement system to the mass of GHG entering the abatement system. When GHGs are formed in an abatement system, destruction or removal efficiency is expressed as one minus the ratio of amounts of exiting GHGs to the amounts entering the system in units of CO2-equivalents (CO2e).
Fab means the portion of an electronics manufacturing facility located in a separate physical structure that began manufacturing on a certain date.
Fluorinated heat transfer fluids means fluorinated GHGs used for temperature control, device testing, cleaning substrate surfaces and other parts, and soldering in certain types of electronics manufacturing production processes. Fluorinated heat transfer fluids do not include fluorinated GHGs used as lubricants or surfactants. For fluorinated heat transfer fluids under this subpart I, the lower vapor pressure limit of 1 mm Hg in absolute at 25 [deg]C in the definition of Fluorinated greenhouse gas in Sec. 98.6 shall not apply. Fluorinated heat transfer fluids used in the electronics manufacturing sector include, but are not limited to, perfluoropolyethers, perfluoroalkanes, perfluoroethers, tertiary perfluoroamines, and perfluorocyclic ethers.
Fully fluorinated GHGs means fluorinated GHGs that contain only single bonds and in which all available valence locations are filled by fluorine atoms. This includes, but is not limited to, saturated perfluorocarbons, SF6, NF3, SF5CF3, C4F8O, fully fluorinated linear, branched, and cyclic alkanes, fully fluorinated ethers, fully fluorinated tertiary amines, fully fluorinated aminoethers, and perfluoropolyethers.
Gas utilization means the fraction of input N2O or fluorinated GHG converted to other substances during the etching, deposition, and/or wafer and chamber cleaning processes. Gas utilization is expressed as a rate or factor for specific electronics manufacturing process sub-types or process types.
Heel means the amount of gas that remains in a gas container after it is discharged or off-loaded; heel may vary by container type.
Input gas means a fluorinated GHG or N2O used in one of the processes described in Sec. 98.90(a)(1) through (4)
Intermittent low-use fluorinated GHG, for the purposes of determining fluorinated GHG emissions using the stack testing method, means a fluorinated GHG that meets all of the following:
(1) The fluorinated GHG is used by the fab but is not used during the period of stack testing for the fab/stack system.
(2) The emissions of the fluorinated GHG, estimated using the methods in Sec. 98.93(i)(4) do not constitute more than 5 percent of the total fluorinated GHG emissions from the fab on a CO2e basis.
(3) The sum of the emissions of all fluorinated GHGs that are considered intermittent low use gases does not exceed 10,000 metric tons CO2e for the fab for that year, as calculated using the procedures specified in Sec. 98.93(i)(1) of this subpart.
(4) The fluorinated GHG is not an expected or possible by-product identified in Table I-17 of this subpart.
Maximum substrate starts means for the purposes of Equation I-5 of this subpart, the maximum quantity of substrates, expressed as surface area, that could be started each month during a reporting year based on the equipment installed in that facility and assuming that the installed equipment were fully utilized. Manufacturing equipment is considered installed when it is on the manufacturing floor and connected to required utilities.
Modeled gas consumed means the quantity of gas used during wafer/substrate processing over some period based on a verified facility-specific engineering model used to apportion gas consumption.
Nameplate capacity means the full and proper charge of chemical specified by the equipment manufacturer to achieve the equipment's specified performance. The nameplate capacity is typically indicated on the equipment's nameplate; it is not necessarily the actual charge, which may be influenced by leakage and other emissions.
Operational mode means the time in which an abatement system is properly installed, maintained, and operated according to the site maintenance plan for abatement systems as required in Sec. 98.94(f)(1) and defined in Sec. 98.97(d)(9). This includes being properly operated within the range of parameters as specified in the site maintenance plan for abatement systems.
Plasma etching is a process type that consists of any production process using fluorinated GHG reagents to selectively remove materials from a substrate during electronics manufacturing. The materials removed may include SiO2, SiOX-based or fully organic-based thin-film material, SiN, SiON, Si3N4, SiC, SiCO, SiCN, etc. (represented by the general chemical formula, SiwOXNyXz where w, x, y and z are zero or integers and X may be some other element such as carbon), substrate, or metal films (such as aluminum or tungsten).
Process sub-type is a set of similar manufacturing steps, more closely related within a broad process type. For example, the chamber cleaning process type includes in-situ plasma chamber cleaning, remote plasma chamber cleaning, and in-situ thermal chamber cleaning sub-types.
Process types are broad groups of manufacturing steps used at a facility associated with substrate (e.g., wafer) processing during device manufacture for which fluorinated GHG emissions and fluorinated GHG consumption is calculated and reported. The process types are Plasma etching/Wafer Cleaning and Chamber cleaning.
Properly measured destruction or removal efficiency means destruction or removal efficiencies measured in accordance with EPA 430-R-10-003 (incorporated by reference, see Sec. 98.7), and, if applicable, Appendix A to this subpart, or by an alternative method approved by the Administrator as specified in Sec. 98.94(k).
The Random Sampling Abatement System Testing Program (RSASTP) means the required frequency for measuring the destruction or removal efficiencies of abatement systems in order to apply properly measured destruction or removal efficiencies to report controlled emissions.
Redundant abatement systems means a system that is specifically designed, installed and operated for the purpose of destroying fluorinated GHGs and N2O gases, or for which the destruction or removal efficiency for a fluorinated GHG or N2O has been properly measured according to the procedures under Sec. 98.94(f)(4), and that is used as a backup to the main fluorinated GHGs and N2O abatement system during those times when the main system is not functioning or operating in accordance with design and operating specifications.
Repeatable means that the variables used in the formulas for the facility's engineering model for gas apportioning factors are based on observable and measurable quantities that govern gas consumption rather than engineering judgment about those quantities or gas consumption.
Representative operating levels means (for purposes of verification of the apportionment model or for determining the appropriate conditions for stack testing) operating the fab, in terms of substrate starts for the period of testing or monitoring, at no less than 50 percent of installed production capacity or no less than 70 percent of the average production rate for the reporting year, where production rate for the reporting year is represented in average monthly substrate starts. For the purposes of stack testing, the period for determining the representative operating level must be the period ending on the same date on which testing is concluded.
Stack system means one or more stacks that are connected by a common header or manifold, through which a fluorinated GHG-containing gas stream originating from one or more fab processes is, or has the potential to be, released to the atmosphere. For purposes of this subpart, stack systems do not include emergency vents or bypass stacks through which emissions are not usually vented under typical operating conditions.
Trigger point for change out means the residual weight or pressure of a gas container type that a facility uses as an indicator that operators need to change out that gas container with a full container. The trigger point is not the actual residual weight or pressure of the gas remaining in the cylinder that has been replaced.
Unabated emissions means a gas stream containing fluorinated GHG or N2O that has exited the process, but which has not yet been introduced into an abatement system to reduce the mass of fluorinated GHG or N2O in the stream. If the emissions from the process are not routed to an abatement system, or are routed to an abatement device that is not in an operational mode, unabated emissions are those fluorinated GHG or N2O released to the atmosphere.
Uptime means the ratio of the total time during which the abatement system is in an operational mode, to the total time during which production process tool(s) connected to that abatement system are normally in operation.
Wafer cleaning is a process type that consists of any production process using fluorinated GHG reagents to clean wafers at any step during production.
Wafer passes is a count of the number of times a wafer substrate is processed in a specific process sub-type, or type. The total number of wafer passes over a reporting year is the number of wafer passes per tool multiplied by the number of operational process tools in use during the reporting year.
Wafer starts means the number of fresh wafers that are introduced into the fabrication sequence each month. It includes test wafers, which means wafers that are exposed to all of the conditions of process characterization, including but not limited to actual etch conditions or actual film deposition conditions. [75 FR 74818, Dec. 1, 2010, as amended at 77 FR 10381, Feb. 22, 2012; 78 FR 68220, Nov. 13, 2013]
Sec. Table I-1 to Subpart I of Part 98--Default Emission Factors for
Threshold Applicability Determination ----------------------------------------------------------------------------------------------------------------
Emission factors EFi
Product type -----------------------------------------------------------------------------
CF4 C2F6 CHF3 C3F8 NF3 SF6----------------------------------------------------------------------------------------------------------------Semiconductors (kg/m\2\).......... 0.90 1.00 0.04 0.05 0.04 0.20LCD (g/m\2\)...................... 0.50 NA NA NA 0.90 4.00MEMS (kg/m\2\).................... NA NA NA NA NA 1.02----------------------------------------------------------------------------------------------------------------Notes: NA denotes not applicable based on currently available information. [75 FR 74818, Dec. 1, 2010, as amended at 78 FR 68221, Nov. 13, 2013]
Sec. Table I-2 to Subpart I of Part 98--Examples of Fluorinated GHGs
Used by the Electronics Industry ------------------------------------------------------------------------
Fluorinated GHGs and fluorinated heat
Product type transfer fluids used during manufacture------------------------------------------------------------------------Electronics.................. CF4, C2F6, C3F8, c-C4F8, c-C4F8O, C4F6,
C5F8, CHF3, CH2F2, NF3, SF6, and
fluorinated HTFs (CF3-(O-CF(CF3)-CF2)n-
(O-CF2)m-O-CF3, CnF2n+2,
CnF2n+1(O)CmF2m+1, CnF2.O, (CnF2n+1)3N).------------------------------------------------------------------------ [77 FR 10381, Feb. 22, 2012]
Sec. 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[GRAPHIC] [TIFF OMITTED] TR13NO13.018
Sec. Table I-4 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 300 mm and 450 mm Wafer Size[GRAPHIC] [TIFF OMITTED] TR13NO13.019 [GRAPHIC] [TIFF OMITTED] TR13NO13.020
Sec. 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 gas i
-----------------------------------------------------------------------------------------------------------
Process type factors NF3
CF4 C2F6 CHF3 CH2F2 C3F8 c- C4F8 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 NAEtch BCF4................................... NA 10.4 10.07 10.08 NA 0.2 NA NA NA 10.3 0.2 NAEtch BC2F6.................................. NA NA NA NA NA 0.2 NA NA NA 10.2 0.2 NACVD Chamber Cleaning 1-Ui................... 0.9 0.6 NA NA 0.4 0.1 0.02 0.2 NA NA 0.1 0.1CVD Chamber Cleaning BCF4................... NA 0.1 NA NA 0.1 0.1 20.02 20.1 NA NA 0.1 0.1CVD 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]
Sec. Table I-6 to Subpart I of Part 98--Default Emission Factors (1-
Uij) for Gas Utilization Rates (Uij) and By-
Product Formation Rates (Bijk) for LCD Manufacturing ----------------------------------------------------------------------------------------------------------------
Process gas i
--------------------------------------------------------------------------------
Process type factors NF3
CF4 C2F6 CHF3 CH2F2 C3F8 c- C4F8 Remote NF3 SF6----------------------------------------------------------------------------------------------------------------Etch 1-Ui...................... 0.6 NA 0.2 NA NA 0.1 NA NA 0.3Etch BCF4...................... NA NA 0.07 NA NA 0.009 NA NA NAEtch BCHF3..................... NA NA NA NA NA 0.02 NA NA NAEtch BC2F4..................... NA NA 0.05 NA NA NA NA NA NACVD Chamber Cleaning 1-Ui...... NA NA NA NA NA NA 0.03 0.3 0.9----------------------------------------------------------------------------------------------------------------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. [75 FR 74818, Dec. 1, 2010, as amended at 78 FR 68225, Nov. 13, 2013]
Sec. Table I-7 To Subpart I of Part 98--Default Emission Factors (1-
Uij) for Gas Utilization Rates (Uij) and By-
Product Formation Rates (Bijk) for PV Manufacturing ----------------------------------------------------------------------------------------------------------------
Process gas i
--------------------------------------------------------------------------------
Process type factors NF3
CF4 C2F6 CHF3 CH2F2 C3F8 c- C4F8 Remote NF3 SF6----------------------------------------------------------------------------------------------------------------Etch 1-Ui...................... 0.7 0.4 0.4 NA NA 0.2 NA NA 0.4Etch BCF4...................... NA 0.2 NA NA NA 0.1 NA NA NAEtch BC2F6..................... NA NA NA NA NA 0.1 NA NA NACVD Chamber Cleaning 1-Ui...... NA 0.6 NA NA 0.1 0.1 NA 0.3 0.4CVD Chamber Cleaning BCF4...... NA 0.2 NA NA 0.2 0.1 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. [75 FR 74818, Dec. 1, 2010, as amended at 78 FR 68225, Nov. 13, 2013]
Sec. Table I-8 to Subpart I of Part 98-- Default Emission Factors (1-
UN2O,j) for N2O Utilization (UN2O,j) ------------------------------------------------------------------------
Process type factors N2O------------------------------------------------------------------------CVD 1-Ui......................................................... 0.8Other Manufacturing Process 1-Ui................................. 1.0------------------------------------------------------------------------
Sec. Table I-9 to Subpart I of Part 98--Methods and Procedures for
Conducting Emissions Test for Stack Systems [GRAPHIC] [TIFF OMITTED] TR13NO13.031 [GRAPHIC] [TIFF OMITTED] TR13NO13.032 [78 FR 68227, Nov. 13, 2013] Sec. Table I-10 to Subpart I of Part 98--Maximum Field Detection Limits
Applicable to Fluorinated GHG Concentration Measurements for Stack
Systems ------------------------------------------------------------------------
Maximum field
Fluorinated GHG Analyte detection limit
(ppbv)------------------------------------------------------------------------CF4................................................... 20C2F6.................................................. 20C3F8.................................................. 20C4F6.................................................. 20C5F8.................................................. 20c-C4F8................................................ 20CH2F2................................................. 40CH3F.................................................. 40CHF3.................................................. 20NF3................................................... 20SF6................................................... 4Other fully fluorinated GHGs.......................... 20Other fluorinated GHGs................................ 40------------------------------------------------------------------------ppbv--Parts per billion by volume. [78 FR 68228, Nov. 13, 2013]
Sec. Table I-11 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 Use With the Stack Test Method (150 mm and 200 mm
Wafers)[GRAPHIC] [TIFF OMITTED] TR13NO13.023 [78 FR 68229, Nov. 13, 2013]
Sec. Table I-12 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 Use With the Stack Test Method (300 mm and 450 mm
Wafers)[GRAPHIC] [TIFF OMITTED] TR13NO13.024 [78 FR 68230, Nov. 13, 2013]
Sec. Table I-13 to Subpart I of Part 98--Default Emission Factors (1-
Uij) for Gas Utilization Rates (Uij) and By-Product Formation Rates (Bijk) for LCD Manufacturing for Use
With the Stack Test Method[GRAPHIC] [TIFF OMITTED] TR13NO13.025 [78 FR 68231, Nov. 13, 2013]
Sec. Table I-14 to Subpart I of Part 98--Default Emission Factors (1-
Uij) for Gas Utilization Rates (Uij) and By-
Product Formation Rates (Bijk) for PV Manufacturing for Use
With the Stack Test Method[GRAPHIC] [TIFF OMITTED] TR13NO13.026 [78 FR 68232, Nov. 13, 2013]
Sec. Table I-15 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 for Use
With the Stack Test Method[GRAPHIC] [TIFF OMITTED] TR13NO13.027 [78 FR 68233, Nov. 13, 2013] Sec. Table I-16 to Subpart I of Part 98--Default Emission Destruction or
Removal Efficiency (DRE) Factors for Electronics Manufacturing ------------------------------------------------------------------------
Default DRE
Manufacturing type/process type/gas (percent)------------------------------------------------------------------------MEMS, LCDs, and PV Manufacturing.................... 60Semiconductor Manufacturing:
Plasma Etch/Wafer Clean Process Type:
CF4......................................... 75
CH3F........................................ 97
CHF3........................................ 97
CH2F2....................................... 97
C2F6........................................ 97
C3F8........................................ 97
C4F6........................................ 97
C4F8........................................ 97
C5F8........................................ 97
SF6......................................... 97
NF3......................................... 96All other carbon-based plasma etch/wafer clean 60
fluorinated GHG....................................Chamber Clean Process Type:
NF3............................................. 88
All other chamber clean fluorinated GHG......... 60N2O Processes:
CVD and all other N2O-using processes........... 60------------------------------------------------------------------------ [78 FR 68234, Nov. 13, 2013]
Sec. Table I-17 to Subpart I of Part 98--Expected and Possible By-
Products for Electronics Manufacturinglg ----------------------------------------------------------------------------------------------------------------
For each stack system for which you
use the ``stack test method'' to If emissions are detected If emissions are not detected, use
calculate annual emissions, you must intermittently, use the following the following procedures:
measure the following: procedures:----------------------------------------------------------------------------------------------------------------Expected By-products:................. Use the measured concentration for Use one-half of the field detection
CF4.................................. ``Xksm'' in Equation I-18 when limit you determined for the
C2F6................................. available and use one-half of the fluorinated GHG according to Sec.
CHF3................................. field detection limit you 98.94(j)(2) for the value of
CH2F2................................ determined for the fluorinated GHG ``Xksm'' in Equation I-18.
CH3F................................. according to Sec. 98.94(j)(2)
for the value of ``Xksm'' when the
fluorinated GHG is not detected.Possible By-products:................. Use the measured concentration for Assume zero emissions for that
C3F8................................. ``Xksm'' in Equation I-18 when fluorinated GHG for the tested
C4F6................................. available and use one-half of the stack system.
c-C4F8............................... field detection limit you
C5F8................................. determined for the fluorinated GHG
according to Sec. 98.94(j)(2)
for the value of ``Xksm'' when the
fluorinated GHG is not detected.---------------------------------------------------------------------------------------------------------------- [78 FR 68234, Nov. 13, 2013]
Sec. Appendix A to Subpart I of Part 98--Alternative Procedures for
Measuring Point-of-Use Abatement Device Destruction or Removal
Efficiency
If you are measuring destruction or removal efficiency of a point-of-use abatement device according to EPA 430-R-10-003 (incorporated by reference, see Sec. 98.7) as specified in Sec. 98.94(f)(4), you may follow the alternative procedures specified in paragraphs (a) through (c) of this appendix.
(a) In place of the Quadrupole Mass Spectrometry protocol requirements specified in section 2.2.4 of EPA 430-R-10-003 (incorporated by reference, see Sec. 98.7), you must conduct mass spectrometry testing in accordance with the provisions in paragraph (a)(1) through (a)(15) of this appendix.
(1) Detection limits. The mass spectrometer chosen for this application must have the necessary sensitivity to detect the selected effluent species at or below the maximum field detection limits specified in Table 3 of section 2.2.7 of EPA 430-R-10-003 (incorporated by reference, see Sec. 98.7).
(2) Sampling location. The sample at the inlet of the point-of-use abatement device must be taken downstream of the process tool and pump package. The sample exhaust must be vented back into the corrosive house ventilation system at a point downstream of the sample inlet location.
(3) Sampling conditions. For etch processes, destruction or removal efficiencies must be determined while etching a substrate (product, dummy, or test). For chemical vapor deposition processes, destruction or removal efficiencies must be determined during a chamber clean after deposition (destruction or removal efficiencies must not be determined in a clean chamber). All sampling must be performed non-intrusively during wafer processing. Samples must be drawn through the mass spectrometer source by an external sample pump. Because of the volatility, vapor pressure, stability and inertness of CF4, C2F6, C3F8, CHF3, NF3, and SF6, the sample lines do not need to be heated.
(4) Mass spectrometer parameters. The specific mass spectrometer operating conditions such as electron energy, secondary electron multiplier voltage, emission current, and ion focusing voltage must be selected according to the specifications provided by the mass spectrometer manufacturer, the mass spectrometer system manual, basic mass spectrometer textbook, or other such sources. The mass spectrometer responses to each of the target analytes must all be calibrated under the same mass spectrometer operating conditions.
(5) Flow rates. A sample flow rate of 0.5-1.5 standard liters per minute (slm) must be drawn from the process tool exhaust stream under study.
(6) Sample frequency. The mass spectrometer sampling frequency for etch processes must be in the range of 0.5 to 1 cycles per second, and for chemical vapor deposition processes must be in the range of 0.25 to 0.5 cycles per second. As an alternative you may use the sampling frequencies specified in section 2.2.4 of EPA 430-R-10-003 (incorporated by reference, see Sec. 98.7).
(7) Dynamic dilution calibration parameters. The quadrupole mass spectrometer must be calibrated for both mass location and response to analytes. A dynamic dilution calibration system may be used to perform both types of mass spectrometer system calibrations using two mass flow controllers. Use one mass flow controller to regulate the flow rate of the standard component used to calibrate the system and the second mass flow controller to regulate the amount of diluent gas used to mix with the standard to generate the calibration curve for each compound of interest. The mass flow controller must be calibrated using the single component gas being used with them, for example, nitrogen (N2) for the diluent. A mass flow controller used with calibration mixtures must be calibrated with the calibration mixture balance gas (for example, N2 or He) if the analyte components are 2 percent or less of the volume of the sample. All calibration mixtures must be National Institute of Standards and Technology Traceable gases or equivalent. They must be calibrated over their range of use and must be operated in their experimentally determined dynamic linear range. If compressed gas standards cannot be brought into the fab, metered gas flows of target compounds into the process chamber, under no thermal or plasma conditions and with no wafer(s) present, and with no process emissions from other tools contributing to the sample location, must then be performed throughout the appropriate concentration ranges to derive calibration curves for the subsequent destruction or removal efficiency tests.
(8) Mass location calibration. A mixture containing 1 percent He, Ar, Kr, and Xe in a balance gas of nitrogen must be used to assure the alignment of the quadrupole mass filter (see EPA Method 205 at 40 CFR part 51, appendix M as reference). The mass spectrometer must be chosen so that the mass range is sufficient to detect the predominant peaks of the components under study.
(9) Quadrupole mass spectrometer response calibration. A calibration curve must be generated for each compound of interest.
(10) Calibration frequency. The mass spectrometer must be calibrated at the start of testing a given process. The calibration must be checked at the end of testing.
(11) Calibration range. The mass spectrometer must be calibrated over the expected concentration range of analytes using a minimum of five concentrations including a zero. The zero point is defined as diluent containing no added analyte.
(12) Operating procedures. You must follow the operating procedures specified in paragraphs (a)(12)(i) through (v) of this appendix.
(i) You must perform a qualitative mass calibration by running a standard (or by flowing chamber gases under non-process conditions) containing stable components such as Ar, Kr, and Xe that provide predominant signals at m/e values distributed throughout the mass range to be used. You must adjust the quadrupole mass filter as needed to align with the inert gas fragments.
(ii) You must quantitatively calibrate the quadrupole mass spectrometer for each analyte of interest. The analyte concentrations during calibration must include the expected concentrations in the process effluent. The calibration must be performed under the same operating conditions, such as inlet pressure, as when sampling process exhaust. If the calibration inlet pressure differs from the sampling inlet pressure then the relationship between inlet pressure and quadrupole mass spectrometer signal response must be empirically determined and applied to correct for any differences between calibration and process emissions monitoring data.
(iii) To determine the response time of the instrument to changes in a process, a process gas such as C2F6 must be turned on at the process tool for a fixed period of time (for example, 20 seconds), after which the gas is shut off. The sample flow rate through the system must be adjusted so that the signal increases to a constant concentration within a few seconds and decreases to background levels also within a few seconds.
(iv) You must sample the process effluent through the quadrupole mass spectrometer and acquire data for the required amount of time to track the process, as determined in paragraph (a)(12)(iii) of this appendix. You must set the sample frequency to monitor the changes in the process as specified in paragraph (a)(6) of this appendix. You must repeat this for at least five substrates on the same process and calculate the average and standard deviation of the analyte concentration.
(v) You must repeat the quantitative calibration at the conclusion of sampling to identify any drifts in quadrupole mass spectrometer sensitivity. If drift is observed, you must use an internal standard to correct for changes in sensitivity.
(13) Sample analysis. To determine the concentration of a specific component in the sample, you must divide the ion intensity of the sample response by the calibrated response factor for each component.
(14) Deconvolution of interfering peaks. The effects of interfering peaks must be deconvoluted from the mass spectra for each target analyte.
(15) Calculations. Plot ion intensity versus analyte concentration for a given compound obtained when calibrating the analytical system. Determine the slope and intercept for each calibrated species to obtain response factors with which to calculate concentrations in the sample. For an acceptable calibration, the R\2\ value of the calibration curve must be at least 0.98.
(b) In place of the Fourier Transform Infrared Spectroscopy protocol requirements specified in section 2.2.4 of EPA 430-R-10-003 (incorporated by reference, see Sec. 98.7), you may conduct Fourier Transform Infrared Spectroscopy testing in accordance with the provisions in paragraph (b)(1) through (17) of this appendix, including the laboratory study phase described in paragraphs (b)(1) through (7), and the field study phase described in paragraphs (b)(8) through (17) of this appendix.
(1) Conformance with provisions associated with the Calibration Transfer Standard. This procedure calls for the use of a calibration transfer standard in a number of instances. The use of a calibration transfer standard is necessary to validate optical pathlength and detector response for spectrometers where cell temperature, cell pressure, and cell optical pathlength are potentially variable. For fixed pathlength spectrometers capable of controlling cell temperature and pressure to within 10 percent of a desired set point, the use of a calibration transfer standard, as described in paragraphs (b)(2) to (17) this appendix is not required.
(2) Defining spectroscopic conditions. Define a set of spectroscopic conditions under which the field studies and subsequent field applications are to be carried out. These include the minimum instrumental line-width, spectrometer wave number range, sample gas temperature, sample gas pressure, absorption pathlength, maximum sampling system volume (including the absorption cell), minimum sample flow rate, and maximum allowable time between consecutive infrared analyses of the effluent.
(3) Criteria for reference spectral libraries. On the basis of previous emissions test results and/or process knowledge (including the documentation of results of any initial and subsequent tests, and the final reports required in Sec. 98.97(d)(4)(i)), estimate the maximum concentrations of all of the analytes in the effluent and their minimum concentrations of interest (those concentrations below which the measurement of the compounds is of no importance to the analysis). Values between the maximum expected concentration and the minimum concentration of interest are referred to below as the ``expected concentration range.'' A minimum of three reference spectra is sufficient for a small expected concentration range (e.g., a difference of 30 percent of the range between the low and high ends of the range), but a minimum of four spectra are needed where the range is greater, especially for concentration ranges that may differ by orders of magnitude. If the measurement method is not linear then multiple linear ranges may be necessary. If this approach is adopted, then linear range must be demonstrated to pass the required quality control. When the set of spectra is ordered according to absorbance, the absorbance levels of adjacent reference spectra should not differ by more than a factor of six. Reference spectra for each analyte should be available at absorbance levels that bracket the analyte's expected concentration range; minimally, the spectrum whose absorbance exceeds each analyte's expected maximum concentration or is within 30 percent of it must be available. The reference spectra must be collected at or near the same temperature and pressure at which the sample is to be analyzed under. The gas sample pressure and temperature must be continuously monitored during field testing and you must correct for differences in temperature and pressure between the sample and reference spectra. Differences between the sample and reference spectra conditions must not exceed 50 percent for pressure and 40 [deg]C for temperature.
(4) Spectra without reference libraries. If reference spectral libraries meeting the criteria in paragraph (b)(3) of this appendix do not exist for all the analytes and interferants or cannot be accurately generated from existing libraries exhibiting lower minimum instrumental line-width values than those proposed for the testing, prepare the required spectra according to the procedures specified in paragraphs (b)(4)(i) and (ii) of this appendix.
(i) Reference spectra at the same absorbance level (to within 10 percent) of independently prepared samples must be recorded. The reference samples must be prepared from neat forms of the analyte or from gas standards of the highest quality commonly available from commercial sources. Either barometric or volumetric methods may be used to dilute the reference samples to the required concentrations, and the equipment used must be independently calibrated to ensure suitable accuracy. Dynamic and static reference sample preparation methods are acceptable, but dynamic preparations must be used for reactive analytes. Any well characterized absorption pathlength may be employed in recording reference spectra, but the temperature and pressure of the reference samples should match as closely as possible those of the proposed spectroscopic conditions.
(ii) If a mercury cadmium telluride or other potentially non-linear detector (i.e., a detector whose response vs. total infrared power is not a linear function over the range of responses employed) is used for recording the reference spectra, you must correct for the effects of this type of response on the resulting concentration values. As needed, spectra of a calibration transfer standard must be recorded with the laboratory spectrometer system to verify the absorption pathlength and other aspects of the system performance. All reference spectral data must be recorded in interferometric form and stored digitally.
(5) Sampling system preparation. Construct a sampling system suitable for delivering the proposed sample flow rate from the effluent source to the infrared absorption cell. For the compounds of interest, the surfaces of the system exposed to the effluent stream may need to be stainless steel or Teflon; because of the potential for generation of inorganic automated gases, glass surfaces within the sampling system and absorption cell may need to be Teflon-coated. The sampling system should be able to deliver a volume of sample that results in a necessary response time.
(6) Preliminary analytical routines. For the proposed absorption pathlength to be used in actual emissions testing, you must prepare an analysis method containing of all the effluent compounds at their expected maximum concentrations plus the field calibration transfer standard compound at 20 percent of its full concentration as needed.
(7) Documentation. The laboratory techniques used to generate reference spectra and to convert sample spectral information to compound concentrations must be documented. The required level of detail for the documentation is that which allows an independent analyst to reproduce the results from the documentation and the stored interferometric data.
(8) Spectroscopic system performance. The performance of the proposed spectroscopic system, sampling system, and analytical method must be rigorously examined during and after a field study. Several iterations of the analysis method may need to be applied depending on observed concentrations, absorbance intensities, and interferences. During the field study, all the sampling and analytical procedures envisioned for future field applications must be documented. Additional procedures not required during routine field applications, notably dynamic spiking studies of the analyte gases, may be performed during the field study. These additional procedures need to be performed only once if the results are acceptable and if the effluent sources in future field applications prove suitably similar to those chosen for the field study. If changes in the effluent sources in future applications are noted and require substantial changes to the analytical equipment and/or conditions, a separate field study must be performed for the new set of effluent source conditions. All data recorded during the study must be retained and documented, and all spectral information must be permanently stored in interferometric form.
(9) System installation. The spectroscopic and sampling sub-systems must be assembled and installed according to the manufacturers' recommendations. For the field study, the length of the sample lines used must not be less than the maximum length envisioned for future field applications. The system must be given sufficient time to stabilize before testing begins.
(10) Pre-Test calibration. Record a suitable background spectrum using pure nitrogen gas; alternatively, if the analytes of interest are in a sample matrix consistent with ambient air, it is beneficial to use an ambient air background to control interferences from water and carbon dioxide. For variable pathlength Fourier Transform Infrared Spectrometers, introduce a sample of the calibration transfer standard gas directly into the absorption cell at the expected sample pressure and record its absorbance spectrum (the ``initial field calibration transfer standard spectrum''). Compare it to the laboratory calibration transfer standard spectra to determine the effective absorption pathlength. If possible, record spectra of field calibration gas standards (single component standards of the analyte compounds) and determine their concentrations using the reference spectra and analytical routines developed in paragraphs (b)(2) through (7) of this appendix; these spectra may be used instead of the reference spectra in actual concentration and uncertainty calculations.
(11) Deriving the calibration transfer standard gas from tool chamber gases. The calibration transfer standard gas may be derived by flowing appropriate semiconductor tool chamber gases under non-process conditions (no thermal or plasma conditions and with no wafer(s) present) if compressed gas standards cannot be brought on-site.
(12) Reactivity and response time checks. While sampling ambient air and continuously recording absorbance spectra, suddenly replace the ambient air flow with calibration transfer standard gas introduced as close as possible to the probe tip. Examine the subsequent spectra to determine whether the flow rate and sample volume allow the system to respond quickly enough to changes in the sampled gas. Should a corrosive or reactive gas be of interest in the sample matrix it would be beneficial to determine the reactivity in a similar fashion, if practical. Examine the subsequent spectra to ensure that the reactivities of the analytes with the exposed surfaces of the sampling system do not limit the time response of the analytical system. If a pressure correction routine is not automated, monitor the absorption cell temperature and pressure; verify that the (absolute) pressure remains within 2 percent of the pressure specified in the proposed system conditions.
(13) Analyte spiking. Analyte spiking must be performed. While sampling actual source effluent, introduce a known flow rate of calibration transfer standard gas into the sample stream as close as possible to the probe tip or between the probe and extraction line. Measure and monitor the total sample flow rate, and adjust the spike flow rate until it represents 10 percent to 20 percent of the total flow rate. After waiting until at least four absorption cell volumes have been sampled, record four spectra of the spiked effluent, terminate the calibration transfer standard spike flow, pause until at least four cell volumes are sampled, and then record four (unspiked) spectra. Repeat this process until 12 spiked and 12 unspiked spectra have been obtained. If a pressure correction routine is not automated, monitor the absorption cell temperature and pressure; verify that the pressure remains within 2 percent of the pressure specified in the proposed system conditions. Calculate the expected calibration transfer standard compound concentrations in the spectra and compare them to the values observed in the spectrum. This procedure is best performed using a spectroscopic tracer to calculate dilution (as opposed to measured flow rates) of the injected calibration transfer standard (or analyte). The spectroscopic tracer should be a component not in the gas matrix that is easily detectable and maintains a linear absorbance over a large concentration range. Repeat this spiking process with all effluent compounds that are potentially reactive with either the sampling system components or with other effluent compounds. The gas spike is delivered by a mass flow controller, and the expected concentration of analyte of interest (AOITheoretical) is calculated as follows:[GRAPHIC] [TIFF OMITTED] TR13NO13.028 Where: AOITheoretical = Theoretical analyte of interest concentration (parts
per million (ppm)).Tracersample = Tracer concentration (ppm) as seen by the Fourier
Transform Infrared Spectrometer during spiking.Tracercylinder = The concentration (ppm) of tracer recorded during
direct injection of the cylinder to the Fourier Transform
Infrared Spectrometer cell.AOIcylinder = The supplier-certified concentration (ppm) of the analyte
of interest gas standard.AOInative = The native AOI concentration (ppm) of the effluent during
stable conditions.
(14) Post-test calibration. At the end of a sampling run and at the end of the field study, record the spectrum of the calibration transfer standard gas. The resulting ``final field calibration transfer standard spectrum'' must be compared to the initial field calibration transfer standard spectrum to verify suitable stability of the spectroscopic system throughout the course of the field study.
(15) Amendment of analytical routines. The presence of unanticipated interferant compounds and/or the observation of compounds at concentrations outside their expected concentration ranges may necessitate the repetition of portions of the procedures in paragraphs (b)(2) through (14) of this appendix. Such amendments are allowable before final analysis of the data, but must be represented in the documentation required in paragraph (b)(16) of this appendix.
(16) Documentation. The sampling and spiking techniques used to generate the field study spectra and to convert sample spectral information to concentrations must be documented at a level of detail that allows an independent analyst to reproduce the results from the documentation and the stored interferometric data.
(17) Method application. When the required laboratory and field studies have been completed and if the results indicate a suitable degree of accuracy, the methods developed may be applied to practical field measurement tasks. During field applications, the procedures demonstrated in the field study specified in paragraphs (b)(8) through (16) of this appendix must be adhered to as closely as possible, with the following exceptions specified in paragraphs (b)(17)(i) through (iii) of this appendix:
(i) The sampling lines employed should be as short as practically possible and not longer than those used in the field study.
(ii) Analyte spiking and reactivity checks are required after the installation of or major repair to the sampling system or major change in sample matrix. In these cases, perform three spiked/unspiked samples with calibration transfer standard or a surrogate analyte on a daily basis if time permits and gas standards are easy to obtain and get on-site.
(iii) Sampling and other operational data must be recorded and documented as during the field study, but only the interferometric data needed to sufficiently reproduce actual test and spiking data must be stored permanently. The format of this data does not need to be interferograms but may be absorbance spectra or single beams.
(c) When using the flow and dilution measurement protocol specified in section 2.2.6 of EPA 430-R-10-003 (incorporated by reference, see Sec. 98.7), you may determine point-of-use abatement device total volume flow with the modifications specified in paragraphs (c)(1) through (3) of this appendix.
(1) You may introduce the non-reactive, non-native gas used for determining total volume flow and dilution across the point-of-use abatement device at a location in the exhaust of the point-of-use abatement device. For abatement systems operating in a mode where specific F-GHG are not readily abated, you may introduce the non-reactive, non-native gas used for determining total volume flow and dilution across the point-of-use abatement device prior to the point-of-use abatement system; in this case, the tracer must be more difficult to destroy than the target compounds being measured based on the thermal stability of the tracer and target.
(2) You may select a location for downstream non-reactive, non-native gas analysis that complies with the requirements in this paragraph (c)(2) of this appendix. The sampling location should be traversed with the sampling probe measuring the non-reactive, non-native gas concentrations to ensure homogeneity of the non-reactive gas and point-of-use abatement device effluent (i.e., stratification test). To test for stratification, measure the non-reactive, non-native gas concentrations at three points on a line passing through the centroidal area. Space the three points at 16.7, 50.0, and 83.3 percent of the measurement line. Sample for a minimum of twice the system response time, determined according to paragraph (c)(3) of this appendix, at each traverse point. Calculate the individual point and mean non-reactive, non-native gas concentrations. If the non-reactive, non-native gas concentration at each traverse point differs from the mean concentration for all traverse points by no more than 5.0 percent of the mean concentration, the gas stream is considered unstratified and you may collect samples from a single point that most closely matches the mean. If the 5.0 percent criterion is not met, but the concentration at each traverse point differs from the mean concentration for all traverse points by no more than 10.0 percent of the mean, you may take samples from two points and use the average of the two measurements. Space the two points at 16.7, 50.0, or 83.3 percent of the measurement line. If the concentration at each traverse point differs from the mean concentration for all traverse points by more than 10.0 percent of the mean but less than 20.0 percent, take samples from three points at 16.7, 50.0, and 83.3 percent of the measurement line and use the average of the three measurements. If the gas stream is found to be stratified because the 20.0 percent criterion for a 3-point test is not met, locate and sample the non-reactive, non-native gas from traverse points for the test in accordance with Sections 11.2 and 11.3 of EPA Method 1 in 40 CFR part 60, Appendix A-1. A minimum of 40 non-reactive gas concentration measurements will be collected at three to five different injected non-reactive gas flow rates for determination of point-of-use abatement device effluent flow. The total volume flow of the point-of-use abatement device exhaust will be calculated consistent with the EPA 430-R-10-003 (incorporated by reference, see Sec. 98.7) Equations 1 through 7.
(3) You must determine the measurement system response time according to paragraphs (c)(3)(i) through (iii) of this appendix.
(i) Before sampling begins, introduce ambient air at the probe upstream of all sample condition components in system calibration mode. Record the time it takes for the measured concentration of a selected compound (for example, carbon dioxide) to reach steady state.
(ii) Introduce nitrogen in the system calibration mode and record the time required for the concentration of the selected compound to reach steady state.
(iii) Observe the time required to achieve 95 percent of a stable response for both nitrogen and ambient air. The longer interval is the measurement system response time. [78 FR 68234, Nov. 13, 2013] Subpart J [Reserved]