Weiring Analysis
Process Window Analysis
Dataset: Several involving 1:1, 1:2 and 1:3 duty cycles
Features: Focus Dose Matrix and Process Window Analysis
TEA Systems Corp.
65 Schlossburg St.
Alburtis, PA 18011
610 682 4146
[email protected]
October 17, 2002
Project Summary
• Program:
• Situation:
Weir Family of products
 Several FEM wafers were measured using tool.
• This data is coded as follows:
•
•
WF#'s 24B2, 54A0: E = 26/1mJ, F = -0.1/.05
CD Target 100nm 1:1
•
•
WF#'s 50G4, 46E4: E = 18/1mJ, F = -0.1/.05
CD Target 100nm 1:2
•
•
WF#'s 38F7, 74E6: E = 16/1mJ, F = -0.1/.05
CD Target 100nm 1:3
 The litho stack is 770A AR40, 2200A 735 resist, and measurement was done at 5pts/fld, both vertical and
horizontal.
 Use the process window analysis to take these data and extract the best dose/focus for each of the 3 pitches.
 Use the following process window to define the best dose/focus:
•
•
•
+/5% in bottom CD
87-90 degrees sidewall angle
220-240 nm resist (t3) thickness
• Summary
 We examined data sets for the 1:1, 1:2 and 1:3 duty cycles.
 Specifications for the SWA and Resist Thickness (T3) were modified to meet the BCD standard
• Problems may lie in the targets or in the metrology software algorithms.
• Non-continuous variation of SWA and T3 (resist) thickness along the focus-dose matrix suggest the problem may be with the
metrology algorithm.
 Site locations on the field do vary, but all data had five points per field.
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -2-
Process Window Summary
• Results for one site per field
Sept. 2003
• Five sites per field
Weir PW
TEA Systems Corp. Confidential
Page -3-
Process Window Specs
Sections
1:1
Variable
T3 (nm)
SWA (°)
BCD (nm)
TCL
UCL
LCL
230.0000 240.0000 220.0000
87.0000 89.0000 82.0000
100.0000 105.0000 95.0000
1:2
Variable
T3 (nm)
SWA (°)
BCD (nm)
TCL
UCL
LCL
190.0000 200.0000 180.0000
87.0000 89.0000 82.0000
100.0000 105.0000 95.0000
• 1:1 data
slide 7
• 1:2 data
slide 21
• 1:3 data
slide 43
• Additional surface plots
slide 54
1:3
Variable
T3 (nm)
SWA (°)
BCD (nm)
Sept. 2003
TCL
UCL
LCL
190.0000 195.0000 180.0000
85.0000 87.0000 84.0000
100.0000 105.0000 95.0000
Weir PW
TEA Systems Corp. Confidential
Page -4-
Focus & Dose Layout
Focus
Dose
Field
Layouts
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -5-
1:1 Duty Cycle, Dense Lines
WF#'s 24B2, 54A0: E = 26/1mJ, F = -0.1/.05
CD Target 100nm 1:1
TEA Systems Corp. Confidential
1:1 Data Ranges
Count
Mean
Median
SEM
Maximum
Minimum
Range
MinMax
Variance
StDev
Mean+3Sigma
SS
Sum
RMSS
Sept. 2003
T2 (nm) T3 (nm)
MSE
BCD (nm) SWA (°) TCD (nm) Z(µm)
225
225
225
225
225
191
225
65.4
216.6
42.2
148.7
79.7
83.3
-173.4
53.8
230.3
125.9
145.6
78.0
81.8
-173.4
0.7
1.2
4.8
2.4
0.3
0.6
0.0
74.2
262.7
251.1
200.0
85.9
113.8
-173.1
33.5
197.9
0.8
91.1
70.1
49.9
-173.6
40.6
64.8
250.2
108.9
15.9
63.9
0.5
74.2
262.7
251.1
200.0
85.9
113.8
-173.6
115.9
338.4
5136.9
1295.9
15.7
70.1
0.0
10.8
18.4
71.7
36.0
4.0
8.4
0.1
97.7
271.8
257.2
256.7
91.6
108.4
-173.7
988516.3 10635446.9 1550645.5 5265700.3 1433907.3 1338203.4 6764856.1
14716.5
48743.4
9486.5
33458.5
17939.8
15907.6 -39014.0
66.3
217.4
83.0
153.0
79.8
83.7
173.4
Weir PW
TEA Systems Corp. Confidential
Page -7-
BCD Range
• Target value for BCD Dose is 100 nm
 Only being achieved up at 32 mj for the 1:1 isolated target structures
 The dose range > 30 mj is the area where the metrology MSE is greatest.
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -8-
MSE variation
Dose
• Model fit errors (MSE) increase dramatically above 30 mj
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -9-
SWA and Focus
T2 (nm)
T3 (nm)
MSE
SWA (°)
BCD (nm)
TCD (nm)
Z(µm)
Family
Focus
Dose
T2 (nm) T3 (nm) MSE
SWA (°) BCD (nm) TCD (nm) Z(µm)
Family
Focus
Dose
1.0000 -0.7116
0.2310
0.1581 -0.5162
-0.2527 -0.0314
0.0000
0.0809
0.6036
-0.7116
1.0000
0.4780 -0.4232
0.1134
-0.4368
0.0222
0.0000 -0.0766
-0.2234
0.2310
0.4780
1.0000 -0.4970
-0.4184
-0.9619
0.0152
0.0000 -0.0709
0.3996
0.1581 -0.4232
-0.4970
1.0000 -0.5316
0.3887 -0.0093
0.0000
0.3146
0.3507
-0.5162
0.1134
-0.4184 -0.5316
1.0000
0.5562
0.0099
0.0000 -0.1259
-0.8770
-0.2527
-0.4368
-0.9619
0.3887
0.5562
1.0000 -0.0101
0.0000
0.1569 -0.5635
-0.0314
0.0222
0.0152 -0.0093
0.0099
-0.0101
1.0000
0.0000 -0.0205
-0.0205
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
1.0000
0.0000
0.0000
0.0809 -0.0766
-0.0709
0.3146 -0.1259
0.1569 -0.0205
0.0000
1.0000
0.0000
0.6036 -0.2234
0.3996
0.3507 -0.8770
-0.5635 -0.0205
0.0000
0.0000
1.0000
• Examination of the focus data shows SWA having the strongest relationship.
 Plot above shows SWA and it median and 20%/ 80% contours of the populations
• We also see covariance between SWA and T3 (Resist) & BCD
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -10-
BCD & T3 (Resist)
• T3 values change linearly.
 There is a region in which values are bimodal from 74 to 80 deg.
• BCD strongly changes as CD size drops below 190 nm
 Target is about 100 nm, this implies that the model may be wrong since we see a discontinuity in SWA in the
BCE = 110 to 90 nm region
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -11-
Parameter setup
• Because of the range restrictions shown in the previous slides we changed the PW centering to:
 Window for SWA was modified to 84 deg.
 Window for BCD was increase set 100 nm (delta 5%)
 T3, Resist thickness was also set per the spec
• NOTE: There is no common process window for these specs for the 1:1 dense line.
 We’ll see why in the next few slides.
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -12-
Resist (T3) thickness and Focus
• Plotted is the resist thickness (T3)
for sites #2 and #5 (shown on
inset). Spec is 220<T3<240
• Notice the bimodal performance
with proper thickness only at the
31 and 32 mj levels
• Graph on right shows T3 boxplot
of population with 20%, 50% &
80% population contour lines
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -13-
Process Window for BCD and Resist (T3)
• This spec for the isolated line results in a very small process window
 Note we used T3=240 nm and BCD=100 nm
 SWA was not included
 Used only two sites on the field, #2 and #5 (shown previous slide
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -14-
SWA spec 87 to 90 deg
• The SWA never quite gets to the spec. SWA even seems drop for the 31,32 mj doses
• As a result, there is no common process window if SWA is included.
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -15-
Horizontal 1:1 process window
• 82<SWA <92
 Spec drives process window to
zero.
 Need to lower SWA spec
T3=230
Swa = 82
BCD Window
T3=220
T3=200
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -16-
Correct Horizontal 1:1 features
• Horizontal 1:1 feature
correct process window
 SWA values had to be
essentially ignored.
• NOTE: Field Center Site
Only
T3=200
SWA=78
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -17-
Problem: 1:1 Horizontal
Lot 54A0
Lot 24B2
Sites #1 & 4
Sites #2,3 & 5
#2
• Window for 5 sites across field don’t overlap.
• Since sites 1& 4 are located at the bottom of the field
 the problem could be with the reticle or with the exposure scan
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
#3
#5
#1
#4
Page -18-
24B2- 1:1 Vertical Features
• 205<T3<230
• 82<SWA<92
• 95<BCD<105
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -19-
Problem: 1:1 Vertical
#2
#3
#5
• Window for 5 sites across
field don’t overlap.
• Since sites 2 & 3 are
located at the top of the
field
#1
 the problem could be
with the reticle or with
the exposure scan
#4
Sites #2 & 3
Sites #1,4 & 5
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -20-
WF#'s 50G4, 46E4: E = 18/1mJ, F = -0.1/.05
CD Target 100nm 1:2
+/5% in bottom CD
87-90 degrees sidewall angle
220-240 nm resist (t3) thickness
TEA Systems Corp. Confidential
1:2 Data Ranges - 50G4H
Count
Mean
Median
SEM
Maximum
Minimum
Range
MinMax
Variance
StDev
Mean+3Sigma
SS
Sum
RMSS
T2 (nm) T3 (nm)
MSE
BCD (nm) SWA (°)
TCD (nm) Z(µm)
225
225
225
225
225
220
225
72.95
199.98
13.89
93.80
86.22
68.78
-174.20
75.71
220.22
251.10
90.10
84.05
62.60
-174.10
0.05
0.70
2.33
1.50
0.07
1.11
0.01
79.19
262.70
496.66
132.75
88.79
101.50
-173.80
72.22
177.74
5.53
47.44
79.31
23.70
-174.40
6.97
84.96
491.13
85.31
9.48
77.80
0.60
79.19
262.70
496.66
132.75
88.79
101.50
-174.40
0.60
109.68
1222.42
505.72
1.03
271.51
0.01
0.77
10.47
34.96
22.49
1.01
16.48
0.11
75.27
231.39
118.78
161.26
89.27
118.21
-174.53
1197577.06 9022396.52 317234.43 2092835.15 1673049.28 1100211.45 6828120.02
16414.16
44994.57
3125.35
21104.49
19400.62
15131.59 -39196.00
72.96
200.25
37.55
96.44
86.23
70.72
174.20
• From the Weir Information spreadsheet
• Spec
 100 +/5% in bottom CD
 87-90 degrees sidewall angle
 220-240 nm resist (t3) thickness
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -22-
MSE measurement error
• Errors range greatly with the
greatest being at the –1 focus (top)
and low energy (left) side of the
wafer
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -23-
BCD v Dose
• Target is 100 nm
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -24-
Resist (T3) v Dose
• Target is 220 to 240 nm so we will not reach Process window on this variable.
• BoxPlot population contours are at 10, 50 & 90% levels.
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -25-
SWA v Dose
• There is a small change in SWA with focus
• The primary response is the spread of measurements with focus
• This is data for all five points in the field.
 The spec of 87 to 90 deg. Is never reached.
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -26-
Setup and data culling – 50G4_H 1:2
• Based on the previous slides data, we set the BCD, SWA and T3 as shown
• Data culling used the MSE variable with a maximum allow value of 20.
 This is shown to have removed 2 data points (upper right figure)
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -27-
Process Window 50G4_H 2:1 X
Field Sites:
Variable
T3 (nm)
SWA (°)
BCD (nm)
5,
TCL
UCL
LCL
210.0000 220.0000 195.0000
86.0000 87.0000 85.0000
100.0000 105.0000 95.0000
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
T3 (nm)
Site: 5
SWA (°) Site: 5
BCD (nm) Site: 5
17.97 mj
19.08 mj
16.71 mj
____ Results ____
PW Rectangle:
...Best Focus
0.1250
...Dept of Focus
0.2100
...Best Dose
20.7000
...Dose Latitude % 2.9000
PW Ellipse:
...Best Focus
0.1000
...Dept of Focus
0.2800
...Best Dose
20.6000
...Dose Latitude % 1.9418
• Process window has 0.21 um Depth of focus and a dose latitude of 2.9%
 Window center: Best focus at 0.125 um and a dose of 20.7 mj
 Only examines the field center test site #5
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -28-
Exposure latitude and DoF
50G4_H
• Depth of focus does not change significantly for increased exposure latitude but there is
not much there to start with.
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -29-
PW 50G4 1:2H – 5 points X
• Dof is about the same but the Dose Latitude is reduced.
• Major influence is the BCD variance.
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -30-
Lot Name:
50G4 -1:2 H 5 Points PW summary
____ Results ____
PW Rectangle:
...Best Focus
0.1150
...Dept of Focus
0.2200
...Best Dose
20.6000
...Dose Latitude % 0.9700
Data Culling
...Variable:
.....Max:
.....Min:
Removed:
...Range:
...Sigma:
Exposure Range
...Dose:
...Focus:
# Points:
50G4__1_2H
03-Oct-03 - 08:26 AM
MSE
20.0000
5.5309
MSE ... Points removed: 2
0.0000
0.0000
18.0000
-0.1000
24.0000
0.2000
217.0000
Process Window Setup
PW Ellipse:
...Best Focus
0.1300
...Dept of Focus
0.2100
...Best Dose
20.8000
...Dose Latitude % 1.9231
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Field Sites:
Variable
T3 (nm)
SWA (°)
BCD (nm)
1, 2, 3, 4, 5,
TCL
UCL
LCL
210.0000 220.0000 195.0000
86.0000 87.0000 85.0000
100.0000 105.0000 95.0000
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
Site: 1
Site: 1
Site: 1
Site: 2
Site: 2
Site: 2
Site: 3
Site: 3
Site: 3
Site: 4
Site: 4
Site: 4
Site: 5
Site: 5
Site: 5
18.49 mj
16.60 mj
13.71 mj
15.12 mj
18.47 mj
16.09 mj
17.99 mj
19.16 mj
16.89 mj
20.08 mj
15.14 mj
8.51 mj
17.97 mj
19.08 mj
16.71 mj
Page -31-
Lot Name:
Vertical 1:2 50G4_Vx
One point – field center
Data on right is from the “Process Window”
spreadsheet
Resist thickness centers about 195 to 210 nm
Data Culling
...Variable:
.....Max:
.....Min:
Removed:
...Range:
...Sigma:
50G4__1_2V
03-Oct-03 - 07:38 AM
MSE
20.0000
5.3689
MSE ... Points removed: 1
0.0000
0.0000
Exposure Range
...Dose:
...Focus:
18.0000
-0.1000
# Points:
44.0000
24.0000
0.2000
Process Window Setup
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Field Sites:
Variable
T3 (nm)
SWA (°)
BCD (nm)
5,
TCL
UCL
LCL
210.0000 220.0000 195.0000
87.0000 89.0000 82.0000
100.0000 105.0000 95.0000
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
T3 (nm)
SWA (°)
BCD (nm)
____ Results ____
PW Rectangle:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
0.1550
0.2400
20.7000
2.9000
PW Ellipse:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
0.1500
0.2800
20.8000
3.8462
Site: 5
Site: 5
Site: 5
16.94 mj
19.85 mj
17.05 mj
Page -32-
Vertical 1:2 50G4_V – 5 sitesX
• Field layout is shown above
• Five sites selected along with
previous specs for SWA and Resist
(T3)
 SWA spec was widened to allow
overlaps.
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -33-
Vertical 1:2 50G4_V – 5 sitesX
Data Culling
...Variable:
.....Max:
.....Min:
Removed:
...Range:
...Sigma:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
MSE
20.0000
5.3689
MSE ... Points removed: 1
0.0000
0.0000
Exposure Range
...Dose:
...Focus:
18.0000
-0.1000
# Points:
24.0000
0.2000
216.0000
Process Window Setup
Field Sites:
Variable
T3 (nm)
SWA (°)
BCD (nm)
1, 2, 3, 4, 5,
TCL
UCL
LCL
210.0000 220.0000 195.0000
87.0000 89.0000 82.0000
100.0000 105.0000 95.0000
• Results summary for five sites in
field from the Weir “Process
Window” spreadsheet
Sept. 2003
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
____ Results ____
PW Rectangle:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
0.1325
0.2650
20.7000
0.9700
PW Ellipse:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
0.1500
0.2700
20.7000
0.9662
Weir PW
TEA Systems Corp. Confidential
Site: 1
Site: 1
Site: 1
Site: 2
Site: 2
Site: 2
Site: 3
Site: 3
Site: 3
Site: 4
Site: 4
Site: 4
Site: 5
Site: 5
Site: 5
17.68 mj
19.86 mj
15.99 mj
15.99 mj
22.08 mj
18.04 mj
17.23 mj
19.74 mj
16.59 mj
18.66 mj
18.90 mj
15.07 mj
16.94 mj
19.85 mj
17.05 mj
Page -34-
50G4 1:2 Vertical Lines – MSE X
MSE, Metrology measurement error
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -35-
46E4_1:2H Response items
• MSE is very uniform with dose so it will not be a good
culling factor with this data set.
• SWA varies from 84 to 89.6 degrees and is influenced by
both dose and focus
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -36-
Lot Name:
46E4_1:2H Center Field Site PW
Data Culling
...Variable:
...Range:
...Sigma:
46E4__1_2H
03-Oct-03 - 09:50 AM
None
0.0000
0.0000
Exposure Range
...Dose:
...Focus:
18.0000
-0.1000
# Points:
45.0000
24.0000
0.2000
Process Window Setup
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Field Sites:
Variable
T3 (nm)
SWA (°)
BCD (nm)
5,
TCL
UCL
LCL
190.0000 200.0000 180.0000
87.0000 89.0000 82.0000
100.0000 105.0000 95.0000
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
T3 (nm)
Site: 5
SWA (°) Site: 5
BCD (nm) Site: 5
____ Results ____
PW Rectangle:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
0.1550
0.2300
21.2500
2.3500
PW Ellipse:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
0.1400
0.3100
21.2000
2.8302
12.52 mj
19.64 mj
17.86 mj
Page -37-
46E4_1:2H – 5 points in field
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -38-
46E4_1:2H – 5 points -Summary
Data Culling
...Variable:
...Range:
...Sigma:
____ Results ____
PW Rectangle:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
0.1425
0.2350
21.1500
1.4200
PW Ellipse:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
0.1350
0.2900
21.1000
1.8957
Sept. 2003
Lot Name:
Weir PW
TEA Systems Corp. Confidential
Exposure Range
...Dose:
...Focus:
# Points:
46E4__1_2H
03-Oct-03 - 10:38 AM
None
0.0000
0.0000
18.0000
-0.1000
24.0000
0.2000
225.0000
Process Window Setup
Field Sites:
Variable
T3 (nm)
SWA (°)
BCD (nm)
1, 2, 3, 4, 5,
TCL
UCL
LCL
190.0000 200.0000 180.0000
87.0000 89.0000 82.0000
100.0000 105.0000 95.0000
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
Site: 1
Site: 1
Site: 1
Site: 2
Site: 2
Site: 2
Site: 3
Site: 3
Site: 3
Site: 4
Site: 4
Site: 4
Site: 5
Site: 5
Site: 5
16.06 mj
20.50 mj
17.61 mj
14.97 mj
20.42 mj
17.57 mj
14.71 mj
19.18 mj
16.67 mj
16.36 mj
20.85 mj
17.99 mj
12.52 mj
19.64 mj
Page
17.86
mj -39-
46E4_1:2Vertical – Field Center
Data Culling
...Variable:
.....Max:
.....Min:
Removed:
...Range:
...Sigma:
MSE
20.0000
4.4411
Variable
0.0000
0.0000
Exposure Range
...Dose:
...Focus:
18.0000
-0.1000
# Points:
45.0000
24.0000
0.2000
Process Window Setup
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Field Sites:
Variable
T3 (nm)
SWA (°)
BCD (nm)
5,
TCL
UCL
LCL
190.0000 200.0000 180.0000
87.0000 89.0000 82.0000
100.0000 105.0000 95.0000
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
T3 (nm)
Site: 5
SWA (°) Site: 5
BCD (nm) Site: 5
____ Results ____
PW Rectangle:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
0.1600
0.2900
21.0500
2.3800
PW Ellipse:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
0.1500
0.2300
21.2000
3.7736
15.35 mj
21.47 mj
18.67 mj
Page -40-
46E4_1:2Vertical – five points
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -41-
Lot Name:
46E4_1:2Vertical – summary
____ Results ____
PW Rectangle:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
0.1350
0.2000
21.2000
1.8900
Data Culling
...Variable:
.....Max:
.....Min:
Removed:
...Range:
...Sigma:
46E4__1_2V
03-Oct-03 - 11:08 AM
MSE
20.0000
4.4411
MSE ... Points removed: 0
0.0000
0.0000
Exposure Range
...Dose:
...Focus:
# Points:
18.0000
-0.1000
24.0000
0.2000
224.0000
Process Window Setup
PW Ellipse:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
Sept. 2003
0.1100
0.2100
21.2000
1.8868
Weir PW
TEA Systems Corp. Confidential
Field Sites:
Variable
T3 (nm)
SWA (°)
BCD (nm)
1, 2, 3, 4, 5,
TCL
UCL
LCL
190.0000 200.0000 180.0000
87.0000 89.0000 82.0000
100.0000 105.0000 95.0000
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
Site: 1
Site: 1
Site: 1
Site: 2
Site: 2
Site: 2
Site: 3
Site: 3
Site: 3
Site: 4
Site: 4
Site: 4
Site: 5
Site: 5
Site: 5
14.76 mj
19.33 mj
16.77 mj
18.07 mj
20.29 mj
18.79 mj
18.76 mj
21.20 mj
19.40 mj
15.20 mj
19.84 mj
17.01 mj
15.35 mj
21.47 mj
18.67
Page
-42-mj
Duty Cycle 1:3 data
TEA Systems Corp. Confidential
38F7_3H Horizontal Field Center
Lot Name: 38F7__1_3H
03-Oct-03 - 08:18 AM
Data Culling
...Variable: MSE
.....Max:
8.0000
.....Min:
0.4655
Removed: MSE ... Points removed: 4
...Range:
0.0000
...Sigma:
0.0000
Exposure Range
...Dose:
16.0000
...Focus:
-0.1000
# Points:
22.0000
0.2000
41.0000
Process Window Setup
Field Sites:5,
Variable TCL
UCL
LCL
T3 (nm)
190.0000 195.0000 180.0000
SWA (°)
85.0000 87.0000 84.0000
BCD (nm) 100.0000 105.0000 95.0000
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -44-
38F7 1:3H Problem with T3 at Site 1
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -45-
38F7 1:3H Problem with T3 at Site 1
• Problem is for data from Focus = -0.1, -0.05 um for dose
>20 mj
 The focus value can be seen by hovering the mouse over the
two points circled on the Dose plot
 Data view is shown to the right
 We’ll restrict the PW analysis for this setup
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Focus
0.2
0.15
0.1
0.05
0
-0.05
-0.1
T3 (nm)
Dose 21 Dose 22
174.72
182.83
179.36
182.93
179.11
182.8
178.82
179.57
175.21
170.97
286.07
285.71
Page -46-
38F7_3:1H restriction method
Data Culling
...Variable:
.....Max:
.....Min:
Removed:
...Range:
...Sigma:
T3 (nm)
230.0000
168.7800
T3 (nm) ... Points removed: 2
0.0000
0.0000
• We’ll use the variable cull
method.
 This removes 2 points as
shown above
• Response is improved
considerably.
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -47-
38F7 1:3H – 5 points
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -48-
Lot Name:
38F7 1:3H – 5 points summary
PW Rectangle:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
0.1675
0.0750
18.8000
2.1300
Data Culling
...Variable:
.....Max:
.....Min:
Removed:
...Range:
...Sigma:
Exposure Range
...Dose:
...Focus:
# Points:
38F7__1_3H
03-Oct-03 - 09:49 AM
T3 (nm)
230.0000
168.7800
T3 (nm) ... Points removed: 4
0.0000
0.0000
16.0000
-0.1000
22.0000
0.2000
212.0000
Process Window Setup
PW Ellipse:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
Sept. 2003
0.1400
0.1200
18.7000
2.1390
Weir PW
TEA Systems Corp. Confidential
Field Sites:
Variable
T3 (nm)
SWA (°)
BCD (nm)
1, 2, 3, 4, 5,
TCL
UCL
LCL
190.0000 195.0000 180.0000
85.0000 87.0000 84.0000
100.0000 105.0000 95.0000
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
1
1
1
2
2
2
3
3
3
4
4
4
5
5
5
12.78 mj
21.33 mj
11.05 mj
12.01 mj
22.50 mj
9.88 mj
14.68 mj
15.72 mj
15.21 mj
15.25 mj
19.08 mj
0.00 mj
11.62 mj
11.05 mj
Page -4913.28 mj
38F7_1:3Vertical - Resist (T3) gating
• MSE seems to vary more at the lower doses
• However, T3 again is the gating variable particularly here at the 1:3 grating
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -50-
38F7_1:3Vertical - Center Field
Data Culling
...Variable:
.....Max:
.....Min:
Removed:
...Range:
...Sigma:
T3 (nm)
200.0000
175.0000
Variable
0.0000
0.0000
Exposure Range
...Dose:
...Focus:
16.0000
-0.1000
# Points:
40.0000
22.0000
0.2000
Process Window Setup
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Field Sites:
Variable
T3 (nm)
SWA (°)
BCD (nm)
5,
TCL
UCL
LCL
190.0000 195.0000 180.0000
85.0000 87.0000 84.0000
100.0000 105.0000 95.0000
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
T3 (nm) Site: 5
SWA (°) Site: 5
BCD (nm) Site: 5
____ Results ____
PW Rectangle:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
0.1450
0.1800
18.7500
1.6000
PW Ellipse:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
0.1600
0.1600
18.8000
2.1277
41.64 mj
8.73 mj
12.01 mj
Page -51-
38F7_1:3Vertical – 5 points
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -52-
Lot Name:
38F7_1:3Vertical – 5 points Summary
PW Rectangle:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
0.1500
0.1300
18.9000
1.0600
Data Culling
...Variable:
.....Max:
.....Min:
Removed:
...Range:
...Sigma:
Exposure Range
...Dose:
...Focus:
# Points:
38F7__1_3V
03-Oct-03 - 10:50 AM
T3 (nm)
200.0000
175.0000
T3 (nm) ... Points removed: 5
0.0000
0.0000
16.0000
-0.1000
22.0000
0.2000
187.0000
Process Window Setup
PW Ellipse:
...Best Focus
...Dept of Focus
...Best Dose
...Dose Latitude %
Sept. 2003
0.1500
0.1500
18.9000
1.0582
Weir PW
TEA Systems Corp. Confidential
Field Sites:
Variable
T3 (nm)
SWA (°)
BCD (nm)
1, 2, 3, 4, 5,
TCL
UCL
LCL
190.0000 195.0000 180.0000
85.0000 87.0000 84.0000
100.0000 105.0000 95.0000
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
IsoFocal Dose:
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
T3 (nm)
SWA (°)
BCD (nm)
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
Site:
1
7.00 mj
1
15.14 mj
1
13.98 mj
2
23.18 mj
2
96.19 mj
2
25.26 mj
3
15.68 mj
3
19.72 mj
3
16.90 mj
4
2.69 mj
4
14.96 mj
4
13.25 mj
5
41.64 mj
5
8.73 mj
Page
-53-mj
5
12.01
Across wafer modeled SWA
• Major modeled SWA variation
across wafer with dose and
focus
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -54-
Modeled BCD variation
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -55-
Residuals to Modeled BCD
• Now we can see
the change across
the field without
the direct influence
of focus and dose.
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -56-
BCD Variation on field by row location
With more points per field,
we could see the scan and
slit variation across the
exposure field.
Sept. 2003
Weir PW
TEA Systems Corp. Confidential
Page -57-