# Threshold Analysis Summary

Total Number of Semiconductor Facilities 175

Comments: Semiconductor facilities include both full-scale and pilot/R&D facilities. Semiconductor Emission Threshold Summary: Emission Threshold (Mt CO 2 Eq) 1,000 10,000 25,000 100,000
Number of Facilities below 41 67 84 120

Percent of Facilities below 23.4% 38.3% 48.0% 68.6%
Total Emissions of Facilities below 20,187 98,467 249,610 1,004,054

Percent of Emissions below 0.4% 1.7% 4.3% 17.5%
Number of Facilities above 134 108 91 55

Percent of Facilities above 76.6% 61.7% 52.0% 31.4%
Total Emissions of Facilities above 5,721,490 5,643,209 5,492,066 4,737,622

Percent of Emissions above 99.6% 98.3% 95.7% 82.5%
Total Number of MEMs Facilities 12 Comments: MEMs facilities are obtained fr om World Fab Watch 2007 database. However, this database does not appear to contain a complete list of MEMs fabrication facilities in the US. MEMs Emission Threshold Summary: Emission Threshold (Mt CO 2 Eq) 1,000 10,000 25,000 100,000
Number of Facilities below 2 8 10 12

Percent of Facilities below 16.7% 66.7% 83.3% 100.0%
Total Emissions of Facilities below 801 25,377 49,952 146,115

Percent of Emissions below 0.5% 17.4% 34.2% 100.0%
Number of Facilities above 10 4 2 0

Percent of Facilities above 83.3% 33.3% 16.7% 0.0%
Total Emissions of Facilities above 145,314 120,739 96,164 0

Percent of Emissions above 99.5% 82.6% 65.8% 0.0%
Total Number of LCDs Facilities 9

Comments: LCD facilities that are assumed to use PFCs include LCOS, a-Si LCDs, OLEDs (assuming active matrix), HTPS, TFT, Single Crystal AMLCD, LTPS. LCDs Emission Threshold Summary: Emission Threshold (Mt CO 2 Eq) 1,000 10,000 25,000 100,000
Number of Facilities below 4 8 9 9

Percent of Facilities below 44.4% 88.9% 100.0% 100.0%
Total Emissions of Facilities below 811 8,720 23,632 23,632

Percent of Emissions below 3.4% 36.9% 100.0% 100.0%
Number of Facilities above 5 1 0 0

Percent of Facilities above 55.6% 11.1% 0.0% 0.0%
Total Emissions of Facilities above 22,821 14,912 0 0

Percent of Emissions above 96.6% 63.1% 0.0% 0.0%
Total Number of PV Facilities 20

Comments: F acilities are estimated (see 'PV' tab for assumptions) and incl ude only silicon based PV (both crystalline and amorphous). Due to time contraints of analysis, we could only rely on report by Burton, 2006 ( PV Emissions during Photovoltaic (PV) Cell Fabricat ion: A Scoping Report). PFC Emissions and PFC using PV plants are likely overestimates (Please see Note 8). PV Emission Threshold Summary: Emission Threshold (Mt CO 2 Eq) 1,000 10,000 25,000 100,000
Number of Facilities below 4 19 19 20

Percent of Facilities below 20.0% 95.0% 95.0% 100.0%
Total Emissions of Facilities below 572 38,699 38,699 73,039

Percent of Emissions below 0.8% 53.0% 53.0% 100.0%
Number of Facilities above 16 1 1 0

Percent of Facilities above 80.0% 5.0% 5.0% 0.0%
Total Emissions of Facilities above 72,466 34,340 34,340 0

Percent of Emissions above 99.2% 47.0% 47.0% 0.0%



# 1TOTAL ELECTRONICS INDUSTRYEmission Threshold (Mt CO2Eq)1,00010,00025,000100,000Number of Facilities below51102122161Percent of Facilities below23.6%47.2%56.5%74.5%Total Emissions of Facilities below22,372171,262361,8931,246,840Percent of Emissions below0.4%2.9%6.0%20.8%Number of Facilities above1651149455Percent of Facilities above76.4%52.8%43.5%25.5%Total Emissions of Facilities above5,962,0915,813,2005,622,5704,737,622Percent of Emissions above99.6%97.1%94.0%79.2%Electronics Tier 1 Default Emission Factors (mean)CF4C2F6CHF3C3F8NF3SF6C6F14Overall Emission Factor (Mt CO2Eq)Source:Semiconductors (kg/m2Si)0.901.000.040.050.040.200.30Semiconductors (Mt CO2Eq/m2Si)23.19IPCC, 2007LCD (g/m2LCD)0.500.904.00LCD (Mt CO2Eq/m2LCD)0.11IPCC, 2007PV-Cells (g/m2PV-Cell)5.000.20PV-Cells (Mt CO2Eq/m2PV-Cell)0.03IPCC, 2007MEMs (kg/m2Si)1.02MEMs (Mt CO2Eq/m2Si)24.41Estimated (seeNote 4)Source: IPCC, 2006Semiconductors (Mt CO2Eq/m2TMLA)3.425PEVM4.0.0701.0701Comment:The upper bound of the 95% confidence interval in this sectoris not used, as the uncertainties vary between 0 and 200% for semiconductors and LCDs. Additionally, nouncertainties are available for heat transfer fluids, MEMs, and PV.Semiconductor Gas Usage CalculationsCF4C2F6CHF3C3F8NF3SF6Emission Factor (Tier 2a)0.90.60.40.40.110.2Gas Usage (kg/m2Si)1.01.70.10.10.41.0Percent of Total GasUsage24%39%2%3%9%24%Source: IPCC, 20062Semiconductor Facility Number Est Actual Area of Si (m 2 ) Emissions from etching/cleaning (MMTCE) Emissions from etching/cleaning

(Mt CO 2 Eq) Emissions from heat transfer fluids (MMTCE) Emissions from heat transfer fluids

(Mt CO 2 Eq) Total Emissions (Mt CO 2 Eq)

Largest

1 42024.28 0.04 139625.66 0.00 14776.26 154401.93

2 37354.92 0.03 124111.70 0.00 13134.46 137246.16

3 26265.18 0.05 183258.68 0.01 19393.85 202652.53

4 21887.65 0.04 152715.57 0.00 16161.54 168877.11

5 21887.65 0.04 132717.10 0.00 14045.15 146762.25

6 21012.14 0.05 174532.08 0.01 18470.33 193002.41

7 19455.69 0.07 271829.33 0.01 28767.08 300596.40

8 18677.46 0.02 62055.85 0.00 6567.23 68623.08

9 17510.12 0.03 104719.25 0.00 11082.20 115801.45

10 17121.00 0.02 56884.53 0.00 6019.96 62904.49

11 15890.43 0.01 52795.95 0.00 5587.28 58383.23

12 14786.32 0.02 78604.08 0.00 8318.49 86922.57

13 14445.85 0.04 141283.29 0.00 14951.69 156234.98

14 14008.09 0.08 308254.45 0.01 32621.86 340876.32

15 13618.98 0.02 81448.30 0.00 8619.49 90067.79

16 12840.75 0.02 68261.44 0.00 7223.95 75485.39

17 11906.88 0.01 39560.60 0.00 4186.61 43747.21

18 11712.32 0.01 32728.25 0.00 3463.56 36191.81

19 11673.41 0.06 228336.63 0.01 24164.34 252500.98

20 11673.41 0.02 81448.30 0.00 8619.49 90067.79

21 11673.41 0.01 54298.87 0.00 5746.33 60045.19

22 11673.41 0.01 46541.89 0.00 4925.42 51467.31

23 11673.41 0.01 34906.42 0.00 3694.07 38600.48

24 11284.30 0.02 78733.36 0.00 8332.17 87065.53

25 11162.70 0.01 29670.45 0.00 3139.96 32810.41

26 10506.07 0.02 62831.55 0.00 6649.32 69480.87

27 10506.07 0.01 54977.61 0.00 5818.15 60795.76

28 10506.07 0.01 54977.61 0.00 5818.15 60795.76 Other (see note 13)

29 10116.96 0.01 40336.30 0.00 4268.70 44605.00

30 9338.73 0.01 43439.10 0.00 4597.06 48036.16

31 8908.27 0.01 32557.51 0.00 3445.49 36002.99

32 8755.06 0.02 61086.23 0.00 6464.62 67550.84

33 8560.50 0.03 119604.90 0.00 12657.51 132262.42

34 8098.43 0.01 37669.84 0.00 3986.51 41656.35

35 7782.27 0.05 195717.11 0.01 20712.29 216429.41

36 7782.27 0.01 46541.89 0.00 4925.42 51467.31

37 7004.05 0.02 58177.36 0.00 6156.78 64334.14

38 7004.05 0.01 41887.70 0.00 4432.88 46320.58

39 6614.93 0.04 145564.60 0.00 15404.77 160969.37

40 6079.90 0.00 16989.33 0.00 1797.94 18787.28

41 6019.10 0.02 81994.77 0.00 8677.32 90672.09

42 5836.71 0.01 40724.15 0.00 4309.74 45033.90

43 5836.71 0.01 34906.42 0.00 3694.07 38600.48

44 5690.79 0.01 20798.41 0.00 2201.05 22999.45

45 5603.24 0.03 109601.58 0.00 11598.88 121200.47

46 5573.91 0.01 20371.24 0.00 2155.84 22527.08



# 3Semiconductor Facility Number Est Actual Area of Si (m 2 ) Emissions from etching/cleaning (MMTCE) Emissions from etching/cleaning

(Mt CO 2 Eq) Emissions from heat transfer fluids (MMTCE) Emissions from heat transfer fluids

(Mt CO 2 Eq) Total Emissions (Mt CO 2 Eq)

47 5471.91 0.00 15290.40 0.00 1618.15 16908.55

48 5471.91 0.00 3636.08 0.00 384.80 4020.88

49 5362.47 0.00 14984.59 0.00 1585.79 16570.38

50 5253.04 0.02 88072.70 0.00 9320.53 97393.23

51 4377.53 0.00 12232.32 0.00 1294.52 13526.84

52 4377.53 0.00 8726.60 0.00 923.52 9650.12

53 4358.07 0.00 11583.76 0.00 1225.88 12809.64

54 4333.75 0.00 14398.90 0.00 1523.80 15922.70

55 4202.43 0.01 35229.08 0.00 3728.21 38957.29

56 3917.89 0.01 27661.52 0.00 2927.36 30588.87

57 3891.14 0.02 57084.16 0.00 6041.09 63125.24

58 3891.14 0.01 43492.69 0.00 4602.73 48095.42

59 3647.94 0.02 56064.80 0.00 5933.21 61998.01

60 3502.02 0.00 9308.38 0.00 985.08 10293.46

61 3283.15 0.01 36696.96 0.00 3883.56 40580.51

62 3283.15 0.00 8726.60 0.00 923.52 9650.12

63 3064.27 0.01 41742.79 0.00 4417.54 46160.33

64 2845.39 0.01 47706.05 0.00 5048.62 52754.67

65 2723.80 0.00 1809.96 0.00 191.54 2001.51

66 2626.52 0.01 22018.18 0.00 2330.13 24348.31

67 2373.59 0.01 39795.81 0.00 4211.50 44007.31

68 2334.68 0.00 6523.90 0.00 690.41 7214.31

69 2279.96 0.00 6371.00 0.00 674.23 7045.23

70 2188.76 0.02 55809.96 0.00 5906.24 61716.20

71 2188.76 0.01 33638.88 0.00 3559.93 37198.80

72 2188.76 0.00 8726.60 0.00 923.52 9650.12

73 2188.76 0.00 6116.16 0.00 647.26 6763.42

74 2188.76 0.00 1454.43 0.00 153.92 1608.35

75 1945.57 0.00 16309.76 0.00 1726.02 18035.78

76 1945.57 0.00 16309.76 0.00 1726.02 18035.78

77 1945.57 0.00 5436.59 0.00 575.34 6011.93

78 1867.75 0.00 14352.59 0.00 1518.90 15871.49

79 1860.45 0.00 6799.48 0.00 719.57 7519.05

80 1751.01 0.01 26911.10 0.00 2847.94 29759.04

81 1751.01 0.00 14678.78 0.00 1553.42 16232.21

82 1751.01 0.00 4892.93 0.00 517.81 5410.74

83 1626.37 0.00 4544.65 0.00 480.95 5025.60

84 1557.22 0.00 4351.42 0.00 460.50 4811.92

85 1556.45 0.01 22833.66 0.00 2416.43 25250.10

86 1367.98 0.00 3822.60 0.00 404.54 4227.14

87 1203.82 0.01 18501.38 0.00 1957.96 20459.34

88 1167.34 0.00 3261.95 0.00 345.20 3607.16

89 1167.34 0.00 3102.79 0.00 328.36 3431.15

90 1167.34 0.00 2327.09 0.00 246.27 2573.37

91 1094.38 0.00 3058.08 0.00 323.63 3381.71

92 1045.74 0.00 2922.17 0.00 309.25 3231.41

93 972.78 0.00 7475.31 0.00 791.09 8266.40

94 972.78 0.00 2718.29 0.00 287.67 3005.96



# 4Semiconductor Facility Number Est Actual Area of Si (m 2 ) Emissions from etching/cleaning (MMTCE) Emissions from etching/cleaning

(Mt CO 2 Eq) Emissions from heat transfer fluids (MMTCE) Emissions from heat transfer fluids

(Mt CO 2 Eq) Total Emissions (Mt CO 2 Eq)

95 963.06 0.00 639.95 0.00 67.72 707.68

96 875.51 0.00 2446.46 0.00 258.90 2705.37

97 836.59 0.00 6428.76 0.00 680.34 7109.10

98 787.96 0.00 9082.50 0.00 961.18 10043.68

99 778.23 0.00 6523.90 0.00 690.41 7214.31

100 766.07 0.00 14984.59 0.00 1585.79 16570.38

101 729.59 0.00 2038.72 0.00 215.75 2254.47

102 622.58 0.00 5219.12 0.00 552.33 5771.45

103 607.99 0.00 8282.30 0.00 876.50 9158.80

104 547.19 0.00 1529.04 0.00 161.81 1690.85

105 486.39 0.00 1359.15 0.00 143.84 1502.98

106 486.39 0.00 1359.15 0.00 143.84 1502.98

107 459.64 0.00 1284.39 0.00 135.92 1420.32

108 420.24 0.02 62384.83 0.00 6602.04 68986.87

109 389.11 0.00 6523.90 0.00 690.41 7214.31

110 350.20 0.00 15126.11 0.00 1600.76 16726.88

111 350.20 0.00 5382.22 0.00 569.59 5951.81

112 322.96 0.00 902.47 0.00 95.51 997.98

113 218.88 0.00 611.62 0.00 64.73 676.34

114 218.88 0.00 611.62 0.00 64.73 676.34

115 194.56 0.00 2854.21 0.00 302.05 3156.26

116 194.56 0.00 1630.98 0.00 172.60 1803.58

117 175.10 0.00 2446.46 0.00 258.90 2705.37

118 153.21 0.00 428.13 0.00 45.31 473.44

119 145.92 0.00 407.74 0.00 43.15 450.89

120 125.49 0.00 350.66 0.00 37.11 387.77

121 109.44 0.00 305.81 0.00 32.36 338.17

122 109.44 0.00 305.81 0.00 32.36 338.17

123 90.35 0.00 3902.54 0.00 413.00 4315.53

124 88.72 0.00 3131.88 0.00 331.44 3463.32

125 87.55 0.00 244.65 0.00 25.89 270.54

126 77.82 0.00 3232.08 0.00 342.04 3574.12

127 77.82 0.00 217.46 0.00 23.01 240.48

128 63.04 0.00 2722.70 0.00 288.14 3010.84

129 62.26 0.00 9242.20 0.00 978.08 10220.28

130 49.81 0.00 695.88 0.00 73.64 769.53

131 48.64 0.00 135.91 0.00 14.38 150.30

132 45.58 0.00 127.37 0.00 13.48 140.85

133 34.14 0.00 4478.26 0.00 473.92 4952.18

134 31.13 0.00 1739.71 0.00 184.11 1923.82

135 31.13 0.00 1304.78 0.00 138.08 1442.86

136 26.27 0.00 4770.60 0.00 504.86 5275.47

137 26.27 0.00 1651.36 0.00 174.76 1826.12

138 21.89 0.00 61.16 0.00 6.47 67.63

139 17.51 0.00 2568.79 0.00 271.85 2840.64

140 17.51 0.00 756.31 0.00 80.04 836.34

141 15.56 0.00 652.39 0.00 69.04 721.43

142 14.01 0.00 587.15 0.00 62.14 649.29



# 5

# 6 Semiconductor Facility Number Est Actual Area of Si (m 2 ) Emissions from etching/cleaning (MMTCE) Emissions from etching/cleaning

(Mt CO 2 Eq) Emissions from heat transfer fluids (MMTCE) Emissions from heat transfer fluids

(Mt CO 2 Eq) Total Emissions (Mt CO 2 Eq)

143 12.45 0.00 521.91 0.00 55.23 577.15

144 10.94 0.00 30.58 0.00 3.24 33.82

145 8.37 0.00 116.89 0.00 12.37 129.26

146 7.78 0.00 1413.51 0.00 149.59 1563.10

147 7.78 0.00 761.12 0.00 80.55 841.67

148 7.78 0.00 336.14 0.00 35.57 371.71

149 7.00 0.00 1272.16 0.00 134.63 1406.79

150 6.23 0.00 260.96 0.00 27.62 288.57

151 6.23 0.00 260.96 0.00 27.62 288.57

152 5.45 0.00 228.34 0.00 24.16 252.50

153 4.86 0.00 271.83 0.00 28.77 300.60

154 4.67 0.00 195.72 0.00 20.71 216.43

155 4.38 0.00 183.48 0.00 19.42 202.90

156 3.50 0.00 636.08 0.00 67.31 703.40

157 3.50 0.00 342.50 0.00 36.25 378.75

158 3.11 0.00 173.97 0.00 18.41 192.38

159 3.11 0.00 43.49 0.00 4.60 48.10

160 2.63 0.00 165.14 0.00 17.48 182.61

161 2.49 0.00 139.18 0.00 14.73 153.91

162 1.95 0.00 285.42 0.00 30.21 315.63

163 1.75 0.00 305.81 0.00 32.36 338.17

164 1.75 0.00 305.81 0.00 32.36 338.17

165 1.75 0.00 134.56 0.00 14.24 148.80

166 1.56 0.00 119.60 0.00 12.66 132.26

167 1.56 0.00 21.75 0.00 2.30 24.05

168 1.31 0.00 247.70 0.00 26.21 273.92

169 0.88 0.00 42.81 0.00 4.53 47.34

170 0.49 0.00 6.80 0.00 0.72 7.51

171 0.39 0.00 38.06 0.00 4.03 42.08

172 0.39 0.00 16.31 0.00 1.73 18.04

173 0.35 0.00 26.91 0.00 2.85 29.76

174 0.22 0.00 16.82 0.00 1.78 18.60

175 0.19 0.00 10.87 0.00 1.15 12.02

Totals 736357.60 1.42 5192197.87 0.15 549478.42 5741676.29

Factors and Assumptions

175 Number of Semiconductor facilities
5,987 Total TMLA of Partner Facilities

7443 Total TMLA All Facilities

0.70 2006 Semiconductor Partner reported emissions (MMTCE)

0.07 2006 Semiconductor Partner estimated heat transfer fluid emissions (MMTCE)

3.66 2006 US Uncontrolled Semiconducto r Emissions (MMTCE). PEVM v4.0.0701.0701

0.39 2006 US estimated heat transf er fluid emissions (MMTCE)

12.02 Total US Emissions Mt CO 2 Eq (Partner reported + Non-Partner uncontro lled, scaled-up to include heat transfer fluids)MEMS Facility Number Substrate Processed (m 2 Si) Emissions (Mt CO 2 Eq)

1 547.19 13,356.07
2 21.89 534.24
3 218.88 5,342.43
4 2,188.76 53,424.28

5 153.21 3,739.70
6 218.88 5,342.43

7 459.64 11,219.10
8 10.94 267.12
9 87.55 2,136.97
10 218.88 5,342.43
11 109.44 2,671.21
12 1,751.01 42,739.43

Totals 5,986.27 146,115.41

LCD Facility Number Substrate Area (m 2 ) Emissions (Mt CO 2 Eq)
1 24,760 2,626 2 12,000 1,273 3 848 90 4 2,121 225
5 1,178 125 6 24,760 2,626
7 3,502 371 8 13,056 1,385 9 140,616 14,912
Totals 222,841 23,632

a-Si only

PV Facility Number m 2 a-Si Emissions (Mt CO 2 Eq)

1 1,000,000 34,340

2 33,333 1,145

3 16,667 572

4 0 0

5 0 0

6 0 0 Crystalline Si

PV Facility Number m 2 a-Si Emissions (Mt CO 2 Eq)

7 76,923 2,642

8 76,923 2,642

9 76,923 2,642

10 76,923 2,642

11 76,923 2,642

12 76,923 2,642

13 76,923 2,642

14 76,923 2,642

15 76,923 2,642

16 76,923 2,642

17 76,923 2,642

18 76,923 2,642

19 76,923 2,642

20 76,923 2,642

Total 2,126,923 73,039



# 7Conversion TypeConversion FactorUnitsCommentsSF6SAR GWP23,900CO2EqNF3GWP8,000CO2Eq17,200 is FAR GWP. 10, 800 is TAR GWP.CF4SAR GWP6,500CO2EqC2F6SAR GWP9,200CO2EqC3F6SAR GWPC3F8SAR GWP7,000CO2EqC4F6SAR GWPC4F8O SAR GWP12,100CO2EqThis GWP is published by a manufacturer, andtherefore, is not used in this report.Source: http://www.future-fab.com/documents.asp?d_ID=1653c-C4F8SAR GWP8,700CO2EqC5F8SAR GWPCHF3SAR GWP11,700CO2EqC6F14SAR GWP7,400CO2EqKg to Mt0.001Mt/kgC to CO23.67CO2/Cunits in one million units1,000,000NAUnits in one thousand units1,000NASquare inches to square feet0.006944ft2/in2Square feet to square meters0.092900m2/ft2Electronics Avg Capacity Utilization100%percentAssumed that all fabs run close to 100% utilization in electronics industry. Need toexplore capacity utilization further.heat transfer fluid emissions factor11%percentAssumed that 9.57% of total semiconductoremissions are from heat transfer fluids(HTFs). Based on proportion of heat transfer fluid emissionsusing 2006 IPCC tier 1default values, we find that 2.22 Mt CO2Eq/square meters of silicon out of 23.19 Mt CO2Eq/square meters of silicon are from HTFs.Therefore, to find the HTF emissions wemultiply etching/cleaning emissions by 11% (or 9.57%/90.43%).mm2to m21.E-06m2/mm2Yellow Highlight Indicates lack of IPCC GWP valuePEVM Emission Factor0.000602601MMTCE/MSI of TMLAPEVM Emission Factor0.002209538Mt CO2Eq/square inches of TMLAPEVM Emission Factor3.425122636Mt CO2Eq/m2 of TMLAPEVM Emission Factor (w/Heat transfer fluids)0.000602601MMTCE/MSI of TMLACapacity Utilization for R&D and Pilot Facilities20%percent8Notes1. No SAR GWP value exists for NF3. We have used NF3 GWP of 8,000 for this analysis (source: Molina et al, Geophysical ResearchLetters, Vol. 22, 1873-6 (1995)). This value is lower than both the TAR (10,800) and FAR (17,200) GWPs for NF3, and is the GWP valueused in the US Inventory for GHG Emissions and Sinks for the semiconductor sector.2. Assumed that pilot/R&Dsemiconductor fabrication facilities manufacture logic devices(when productclass was notspecified).3. Assumed that all full-scale semiconductor facilities operate at 100% of design capacity and all pilot/R&D facilitiesoperate at 20% of design capacity.4. No IPCC Tier 1 default emission factor for MEMS. Assumed that MEMS emission factor is equal to 1.2 x (1/.24) x IPCC Tier1 SF6emission factor for semiconductor devices. We made this assumption because anisotropic etches are desired forMEMS, which means Bosch process is desired (which uses SF6/C4F8process recipe). C4F8has a high utilization, whereas,SF6has low utilization. Therefore, we have assumed the emission rate of MEMS is equal to that of SF6etching insemiconductors. However, SF6usage (in kgs of gas) in semiconductor manufacturing accounts for only 24% of total PFC gasusage (whereas we assume it accounts for 100% of usagein MEMS manufacturing). Therefore, the semiconductor SF6emission factor is scaled-up by 1/.24. Additionally, the MEMS emission factor was scaled up by an additional factor of 1.2 toaccount for increased SF6usage in MEMS manufacturing as compared to semiconductor manufacturing.5. Assumed that only MEMS fabs that usePFCs (as opposed to liquid etchants) are those that manufacture wafers of at least150 mm in diameter.6. WFW appears to not contain a complete listing of U.S. MEMSfabs in the U.S. for the year 2007. A better database would bethe YoleDevelopments (France) database on MEMs devices of the World, which is as comprehensive towards MEMS as WFW is towards semiconductors.See: http://www.yole.fr/pagesAn/products/wordmem.asp for March 2008 Report details.7. LCD substrate area is multiplied by 2 as the IPCC 2006 default emission factor is in terms of total LCD area (including boththe TFT substrate area and the color filter substrate area, even though only the TFT substrate area utilizes PFCs).8. We relied on a report by Burton, 2006 (PV Emissions during Photovoltaic (PV) Cell Fabrication: A Scoping Report).Information was limited at the time the scoping report was written. Since that timewe haven't learned any more about the useof PFCs in crystalline silicon (and the 2006 report itself had little information on use of PFCs in crystalline silicon). On the thinfilm side, although we don't know much about PFC use, we know that thin film production has greatly increased in the form ofamorphous si- CIGS and CdTe. For the latter two types of technology, PFCs are not used. For amorphous silicon, PFCs areonly used if the silicon is depositedin PECVD chambers and the chambers are cleaned with PFCs during PECVD.910Notes9. Due to lack of data of crystalline PV plants, we haveassumed that all plants have a capacity of approximately 10MW(Expert Judgment). We have determined the total number of facilities in the US by dividing our estimate for total crystallinePVproduction capacity in the US by 10MW.Further analysis/purchasing of researchreports could clarify the distribution ofcrystalline PV facilities in the US.10. We have assumed 100% utilization efficiency for all electronics sectors due to insufficient data to determine exact capacityutilization.11. The upper bound of the 95% confidence interval in this sector is not used to determine alternative threshold capacities, asno exact uncertainty for 2006 IPCC defaultfactors exist for semiconductors and LCDs (only information available is thatuncertainties vary between 0 and 200% for semiconductors and LCDs). Additionally, no uncertainties are available for heattransfer fluids, MEMS, and PV.12. We assumed that 9.57% of total semiconductor emissions are from heat transfer fluids (HTFs). Based on proportion ofheat transfer fluid emissions using 2006 IPCC tier 1 default values, we find that 2.22 Mt CO2Eq/square meter of silicon out of23.19 Mt CO2Eq/square meter of silicon are from HTFs. Therefore,to find the HTF emissions we multiplied etching/cleaningemissions by 11%(or 9.57%/90.43%).13. We have assumed that the “largest” semiconductor facilitiesinclude an estimated 29 facilities(as opposed to 28) to account for net of expected fab closingsand openings.