EUV Platform Readiness Progress and Challenges
Klaus Schuegraf, Daniel Brown, Uwe Stamm & Christian Wagner
Maui, Hawaii June 25, 2014
2014 International Workshop on EUV Lithography
Confidential
Agenda
June 25, 2014
Slide 2
• EUV overview
• Source power and availability technology development
Confidential
EUV overview: Progress toward production insertion
• Multiple customers are qualifying EUV for insertion at the 10 nm logic node
• For process development, customers typically require 100 wafers per day,
increasing to 500 wafers per day on average for production qualification
• We have provided customers with that process development capability
• In 2016 we will provide our customers with the productivity needed for volume
production
Confidential
• 6 NXE:3300B systems fully qualified
and shipped to customers
• 5 more NXE:3300B systems being
integrated
• 4th generation NXE system
(NXE:3350B) integration ongoing NXE:3300B
June 25, 2014
Slide 3
NXE:3300B systems are exposing at customer sites Confidential
June 25, 2014
Slide 4
NXE:3300B resolution for single exposures Dense line spaces, regular and staggered contact holes
Confidential
13nm HP
14nm HP
Dipole30,
Chemically Amplified Resist
(CAR)
Quasar 30 (CAR)
17nm HP
18nm HP
18nm HP
19nm HP
Large Annular (CAR)
Dipole45,
Inpria Resist
13nm HP
14nm HP
June 25, 2014
Slide 5
EUV meets aggressive 2D logic imaging requirements
0
10
20
30
40
50
60
70
80
20 nm 16 nm 10 nm 7 nm
CD
[nm
] CD requirements by node
Tip-to-tip Tip-to-line Lines and spaces
31nm
22nm
16nm
* Single Expose (SE) using high dose resist @ ~50mJ/cm2
EUV (SE)*
Confidential
June 25, 2014
Slide 6
Full wafer
Matched Machine Overlay
NXE:3300B – NXT:1950i
No subrecipes used
Good matched machine overlay performance on
multiple systems (NXE:3300B to immersion)
Systems
Matc
hed M
achin
e
Overlay [
nm
]
10 nm99.7%x: 3.4 nmy: 3.3 nm
MMO S2F Stepper Filtered Machine 3
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
1 2 3 4
Overlay X Overlay Y
Confidential
June 25, 2014
Slide 7
Laser Produced Plasma (LPP) source architecture
Pre-Pulse Is
ola
tor
Pre
Amp PA Seed o
ptics
op
tics
PA op
tics
op
tics
PA op
tics
Vessel
with Collector and Tin Droplet
Generator
Focusing
Optics
Beam Transport System Fab Floor
Sub-Fab Floor Drive Laser
PA op
tics
Ele
ctr
on
ics
Ele
ctr
on
ics
CO2 laser
operating at
high repetition
rate
June 25, 2014
Slide 8
Confidential
Ramping source production for NXE:3300B vessels Confidential
June 25, 2014
Slide 9
Multiple development and integration sources
supporting NXE:3300B source production Confidential
NXE:3300B
Drive Laser NXE:3300B
Source
June 25, 2014
Slide 10
NXE:3100 continues to be used for cycles of learning 6 systems operational with source availability >70%
Confidential
Cu
mu
lati
ve
wa
fers
ex
po
se
d o
n N
XE
:31
00
2011 2012 2013 2014
June 25, 2014
Slide 11
NXE:3100: collector lifetime is key to high availability Field collector performance improved with changes in capping layer
technology and vacuum control
Confidential
No Cap
Cap type B
Champion
Cap type A
• 70 Gpulse average lifetime in 2013 for NXE:3100 field
sources
• Initial usage ~10Gpulse per month
• Lifetime requirement >100Gpulse in high volume use
• 5steradian near-normal incidence
graded multilayer coated collector
• Collector reflectivity maintained using
hydrogen to prevent ion damage and
tin vapor deposition
June 25, 2014
Slide 12
Agenda
• EUV overview
• Source power and availability technology development
Confidential
June 25, 2014
Slide 13
MOPA Prepulse LPP source architecture for NXE:3300B
Pre-Pulse Is
ola
tor
Pre
Amp PA Seed o
ptics
op
tics
PA op
tics
op
tics
PA op
tics
Power Amplifier
Vessel
With Collector, Droplet
Generator and Metrology
Focusing
Optics
Beam Transport System Fab Floor
Sub-Fab Floor
MOPA - Master Oscillator Power Amplifier
Master Oscillator
PA op
tics
CO2 laser
operating at
50kHz
Ele
ctr
on
ics
Ele
ctr
on
ics
Controllers for Dose
and Prepulse
June 25, 2014
Slide 14
Confidential
Source power
Drive laser power
Conversion efficiency
Dose margin
Optical transmission
Source availability
Drive laser reliability
Droplet generator reliability & lifetime
Automation
Collector protection
Source power and availability drive productivity Technology development work is ongoing to improve all aspects
Confidential
Focus of today’s
presentation
June 25, 2014
Slide 15
Source power scaling Confidential
June 25, 2014
Slide 16
Scaling parameter
EUV Power in Burst (W) 40 80 250
Laser Power (kW) 20 26 43
Conversion Efficiency (%) 2.5 3.5 4.5
Dose margin (%) 35 20 10
Key scaling parameters are:
• Laser power
• Conversion efficiency
• Dose margin
Drive laser: High-power amplifier chain validated Confidential
HPDL Top View
Seed table
• First HPDL prototypes delivered and integrated with
current seed table
• >30kW total CO2 power
• Good beam quality
• Together with new seed system higher EUV power
June 25, 2014
Slide 17
Conversion efficiency: Optimizing pre-pulse to create a
more efficient target
Target expansion fills main
pulse beam waist
Confidential
Prepulse (low energy)
Mainpulse (high energy)
Target shape changes
from droplet to disk
June 25, 2014
Slide 18
High CE demonstrated with optimized pre-pulse
June 25, 2014
Slide 19 ~4% conversion efficiency achieved at high duty cycle Confidential
Slide 19
Data taken on MOPA Prepulse development source
High CE requires control of:
• Target conditioning
• Targeting dynamics
• Focus control
Advanced Seed
Standard Seed
Best conversion
efficiency achieved at
target size of ~400µm CE>~4%
Dose margin: Closing the gap between ‘open loop’ and
stabilized power Confidential
Closed Loop Power Po
we
r Margin
Time • Plasma and gas-dynamic forces distort
droplet trajectories causing mis-
targeting, low CE and energy instability
• Controls that compensate for these
forces enable closed loop operation
with reduced margin
• Margin is the difference between
unstabilized open loop power and
stabilized closed loop power
• Required for dose control
0 1 2 3 4 5 6-1
-0.5
0
0.5
1
Ave
rage
Dos
e E
rror
[%
]
Time [Hours]
Open Loop Power
June 25, 2014
Slide 20
• Comparison: EUV stabilization energy controller vs current controller
• Maximizing available power with reduced dose margin using advanced
dose control software
0 50 100 150 200-60
-50
-40
-30
-20
-10
0
10
Time [s]
Dose E
rror
[%]
Advanced controller demonstrated at <10% dose margin Existing controller: good performance at ~35% margin
Tests on MOPA/Pre-pulse development source
Confidential
Current controller
35% dose margin: In-spec
June 25, 2014
Slide 21
150 200 250 300 350 400 450-60
-50
-40
-30
-20
-10
0
10
Time [s]
Dose E
rror
[%]
~75W open loop power
70W stabilized
~60W open loop power
40W stabilized
EUV Stabilization controller
6% dose margin: In-spec
Current controller
6% dose margin: Out-of-spec
0 1 2 3 4 5 6-4
-3
-2
-1
0
1
2
3
4
Time [min]
Do
se
Err
or
[%]
0 1 2 3 4 5 666
67
68
69
70
71
72
73
74
Time [min]
Po
we
r [W
]
Source power
Drive laser power
Conversion efficiency
Dose margin
Optical transmission
Source availability
Drive laser reliability
Droplet generator reliability & lifetime
Automation
Collector protection
Source power and availability drive productivity Technology development work is ongoing to improve all aspects
Confidential
Focus of today’s
presentation
June 25, 2014
Slide 22
Automation: Stable power, good dose control NXE:3300B stand-alone source under full automation for
improved availability
Confidential
0 500 1000 1500 2000 2500 3000 3500 4000
38
40
42
44
time [sec]
Pow
er
[W]
10-2
10-1
100
0
20
40
60
80
100
Dose Error [%]
Good D
ies (
Exposure
s)
[%]
Error
1.0% Error
99.9%
99.9% die yield
(simulated)
~40W stable power
(x, y, z, t and E loops
closed)
Simulated wafer lot exposures
at 30mJ/cm2 resist dose
June 25, 2014
Slide 23
No collector reflectivity degradation after >5 Gpulses NXE:3300B source collector protection test, all control loops closed
Confidential
Far-field EUV image
Initial Far-field EUV image
after 6.3Gp
NXE:3300B stand-alone
source operating in San Diego • ~40W, 90% EUV duty cycle
• All control loops closed
• Simulated wafer exposure lots
at 25mJ/cm2 dose
~500 simulated wafer exposures over
6.3Gpulses
6.3Gp 0Gp
June 25, 2014
Slide 24
In-situ collector cleaning Effectiveness of product configuration confirmed
Confidential
June 25, 2014
Slide 25
Off-line cleaning using NXE:3300B source
vessel with product configuration hardware Reflectivity restored within 0.8% of original
Cleaning in off-line MOPA Prepulse development vessel
Field collector
cleaned in
NXE:3300 source
vessel test rig
Start End
Start End
Source power
Drive laser: high-power amplifier chain validated
High conversion efficiency of ~4% demonstrated
Dose margin <10% with advanced controller demonstrated
Optical transmission
Source availability
Drive laser reliability
Droplet generator reliability & lifetime
Full automation with good dose control demonstrated
Collector protection: protection & in-situ cleaning validated
Summary: Source power and availability technology
development for improved productivity Confidential
June 25, 2014
Slide 26