The Tier 1 emission standard shall apply to an owner or operator of a semiconductor operation that processes more than 37.7 million square centimeters of wafer surface area per calendar year. The Tier 1 emission standard shall also apply to the owner or operator of a semiconductor operation that begins operation after January 1, 2010.
An owner or operator must express fluorinated gas emissions in CO2e units. The kilograms of fluorinated gas emissions are determined using the Tier 2b calculation method in the 2006 Intergovernmental Panel on Climate Change (IPCC) Guidelines for National Greenhouse Gas Inventories, incorporated by reference herein. The IPCC 1996 Second Assessment Report (SAR) provides the GWP values used to calculate fluorinated gas emissions, with the exception of NF3 which is based on the GWP value from the IPCC Fourth Assessment Report.
An owner or operator of a semiconductor operation may request that the permitting agency approve the use of an alternative destruction removal efficiency (DRE) value that exceeds the default DRE value in the Tier 2b calculation method. An alternative DRE must be based on independent third party measured results for the emission control equipment used by the operation.
The kilograms of fluorinated gas emissions from CVD chamber cleaning and etching are converted to million metric tons of CO2 equivalent (MMT CO2e) using the following formula:
Total Fluorinated Gas Emissions in MMT CO2e = [SIGMA] Ei(GWP100)i/109 Where:
E = the kilograms of fluorinated gas emitted using the Tier 2b method
i = the fluorinated gas
GWP100 = the GWP of the fluorinated gas
109 = the number of kilograms per million metric ton
For an operation emitting more than 0.0008 MMT CO2e per calendar year, total fluorinated gas emissions in MMT CO2e are converted to kilograms of CO2 equivalents per square centimeter (Kg CO2e/cm2) using the following formula:
Emissions in Kg CO2e/cm2 = (MMT CO2e)(109) / [SIGMA][([PHI]rn2 Wfn)/100]
Where:
109 = the number of kilograms per million metric ton
[PHI] = 3.1416
rn = one half the diameter in millimeters of a given size wafer n = diameter of a wafer in millimeters
Wfn = the number of wafers of a given size processed in the calendar year
100 = the number of square millimeters per square centimeter
Table 1
Emission Standards for Semiconductor Operations Effective January 1, 2012
CVD Chamber Cleaning and Etching Processes
Wafer Surface Area Processed (Million Square Centimeters Per Calendar Year) | Maximum Emissions Limit Per Square Centimeter for a Calendar Year (Kg CO2e/cm2) |
Tier 1: >37.7 | 0.2 |
Tier 2: >3.7 and [LESS THAN EQUAL TO]37.7 | 0.3 |
Tier 3: [LESS THAN EQUAL TO]3.7 | 0.5 |
Cal. Code Regs. Tit. 17, § 95323
Note: Authority cited: Sections 38501, 38510, 38560, 38560.5, 38580, 39600 and 39601, Health and Safety Code. Reference: Sections 38501, 38505, 38510, 38550, 38551, 38560, 38560.5, 39600 and 39601, Health and Safety Code.