draft 020210 pw10 picosecond laser...
TRANSCRIPT
PicosecondPicosecond laser processing of laser processing of semiconductor and thin film devicessemiconductor and thin film devices
Brian BairdBrian BairdBrian BairdBrian Baird
Summit Photonics LLCSummit Photonics LLC
January 26, January 26, 20102010
Summit Photonics
Paper 7580-25, Fiber Lasers VII: Technology, Systems, and Applications, Proceedings of SPIE Vol. 7580, LASE SPIE Photonics West 2010
TopicsTopics
• Introduction and Source Architectures
• Semiconductor Micromachining
• Memory Processing
• Thin Film Device Microprocessing
SSummit PhotonicsSummit Photonics
• Thin Film Device Microprocessing
• c-Si and Thin Film Solar Cells
• Emerging Technology and Processes
Pulsed Solid State PhotonicsPulsed Solid State PhotonicsEssential Essential MicroelectonicsMicroelectonics ToolsTools
• Pulsed lamp-pumped Nd:YAG lasers entered the trimming and marking laser systems markets in the 1970s.
• Pulsed diode-pumped Nd:YLF lasers entered the commercial systems market in 1988 (Spectra-Physics Model 7950 employed on the ESI Model
S
commercial systems market in 1988 (Spectra-Physics Model 7950 employed on the ESI Model 9000)
• In the mid 1990s, 266 nm and 355 nm pulsed harmonic solid state lasers achieved wide adoption.
• Over the past decade, ps DPSS, hybrid, and fiber lasers have begun to enter the industrial laser processing market.
Summit Photonics
psps Materials ProcessingMaterials ProcessingA
ve
rag
e P
ow
er
10W
100W
High speed processing –
Micro-via, drilling, dicing,
cutting
Quasi-CW 532nmAnd UV systems-SC Inspection, ,trimming, ...
Trumpf TruMicro –
Coherent Talisker Hybrid
Lumera , TBP, HIQ DPSS
Fianium, IMRAuFibre
SP–PanteraHybrid.
Coherent PaladinDPSS
High speed processing –
Medical, Polymers,
Scribing ....
SeedSources
Bio-
Medical
S
Pulse EnergyPulse Energy
Ave
rag
e P
ow
er
100uJ10uJ1uJ100nJ10nJ1nJ 1mJ
1W
0.1W
DPSSFianium -FP1060, FP532Fibre
Ultrafast Ultrafast FiberFiber lasers lasers Comfort Zone NowComfort Zone Now
Fianium -UVP 355Fibre
Summit Photonics
Ultrafast Ultrafast ProcessTimescalesProcessTimescales
SSummit PhotonicsSummit Photonics
psps Solid State PhotonicSolid State PhotonicSource ArchitecturesSource Architectures
• DPSS MOPAs and regenerative amplifiers
• Hybrids (tandem amplifiers) employing fiber front end coupled to solid state
S
fiber front end coupled to solid state amplifiers
• All fiber
Summit Photonics
Time Bandwidth Time Bandwidth psps DPSS LasersDPSS LasersAmplifier domainlow speed
1 mJ
100 µJ
10 µJ
Pu
lse e
nerg
y
FORTIS™
FUEGO™
S
Oscillator domainlow energy
CHEETAH™
1 kHz 10 kHz 100 kHz 1 MHz 10 MHz 100 MHz
Repetition rate
1 µJ
100 nJ
10 nJ
1 nJ
Pu
lse e
nerg
y
ARGOSDUETTO™
Summit Photonics
Tandem Amplifier ConceptTandem Amplifier ConceptA Hybrid Approach to Peak Power Scaling A Hybrid Approach to Peak Power Scaling
• Employ DPSS amplifier to boost peak power and output energy per pulse while producing well defined tailored temporal pulse output
• Match gain spectrum of fiber and solid state medium to allow stable harmonic operation
S
M-MOFPADPSS Amplifier
Harmonic module
Summit Photonics
Tandem Amplifier 32 Experimental Setup
2-Stage, single pass
Nd:YVO4 Amplifier1
MOFPA
M. Frede, Opt. Exp. 15, 459-465 (2007)
MOFPA
Summit Photonics
Amplifier ConceptAmplifier ConceptNew: Single or double passLow Input Power Module LP
Standard ModuleMP
New: High Power Module HP
< 100 mW 1-2 W 10-20 W > 50 W
S
FI
< 100 mW 1-2 W 10-20 W > 50 W
Flexible power scaling (10-100W) by type and number of modulescw to ps-pulse regimes
Summit Photonics
MPMP--Module CW Single Pass ResultsModule CW Single Pass Results
25
30
35
3
4
Nr.of stages:
Ou
tput
Pow
er
[W]
40
50
60
70
Ou
tpu
t P
ow
er
[W]
40
50
S
0,0 0,2 0,4 0,6 0,8 1,0 1,2 1,4 1,6 1,8 2,0
0
5
10
15
20
1
2
Ou
tput
Pow
er
[W]
Input Power [W]
0 2 4 6 8 10 12 14 16 18 20
0
10
20
30
40
Ou
tpu
t P
ow
er
[W]
Input Power [W]
0
10
20
30
Ga
in
Summit Photonics
Talisker Talisker -- Picosecond Industrial Hybrid LaserPicosecond Industrial Hybrid Laser
SSummit Photonics
The Promise of AllThe Promise of All--FiberFiber psps LasersLasers
S
• Traditional ultrafast lasers have often been bulky, complex and expensive• Benefits of fiber lasers – compactness, reliability, and reduced maintanence• Improvements in DPSS and emergence of fiber lasers enables industrial applications
Summit Photonics
Fianium FP1060 Fianium FP1060 psps MOFPAMOFPA
S
• Flexible repetition rates
• > 1 MHz for high throughput
• Energy per pulse > 10 uJ
• Excellent beam quality
• Single shot and burst mode for flexibility and control
• Peak powers up to 500 KW4 MW
Summit Photonics
TopicsTopics
• Introduction and Source Architectures
• Semiconductor Micromachining
• Memory Processing
• Thin Film Device Microprocessing
SSummit PhotonicsSummit Photonics
• Thin Film Device Microprocessing
• Processing of c-Si and Thin Film Solar Cells
• Emerging Technology and Processes
psps Scribing Results in UltraScribing Results in Ultra--Low k DevicesLow k Devices
S
Very low debris, minimal HAZ, High die fracture strength
Summit Photonics
8
10
12
14
16
rem
oval ra
te [m
m³/
min
]
6 Burst
4 Burst
2 Burst
1 Burst
200µm
50µm
Hyper Rapid 50, 1064 nm, constant average power of 50W
Silicon Micromachining – Lumera Hyper-Rapid
S
SPIE SPIE 75857585--16 16 MicroMicro-- and Nanomachining , Photonics West 2010and Nanomachining , Photonics West 2010
200 400 600 800 10000
2
4
6
rem
oval ra
te [m
m³/
min
]
repetition rate [kHz]
• High rep. rate + burst: 14x removal rate
Eff. ablation rate:HYPER-RAPID 50 > 20 mm3/min
Summit Photonics
Wafer Scribing Wafer Scribing –– FP1060FP1060--HEHE
• 1064 nm• 10 ps• 5 MHz• 600 mm/sec
S
• Scribing Low-K region • High repetition rate, low energy – pulse overlap• No Delamination, low debris – very clean scribe
• 600 mm/sec•1.1 uJ
Summit Photonics
ps laser Marking of Silicon wafers
Product Tangerine fs Tangerine ps Tangerine sp
Pulse energy > 10 µJ > 10 µJ > 0.5 µJ
Repetition rate
2 MHz 2 MHz 30 MHz
Pulse duration
< 700 fs 10 ps < 100 fs
Footprint (cm)
120x40 120x40 120x40
16x16 DataMatrix
S
SEM x385x2540
16x16 DataMatrixmarkingProcessing time 72msDimensions 0.5x0.5mm2µJ @2MHz 100pls/point
Summit Photonics
TopicsTopics
• Introduction and Source Architectures
• Semiconductor Micromachining
• Memory Processing
• Thin Film Device Microprocessing
SSummit PhotonicsSummit Photonics
• Thin Film Device Microprocessing
• c-Si and Thin Film Solar Cells Processing
• Emerging Technology and Processes
Laser Repair System Laser Repair System FabFab InstallationInstallation
~ 100 laser memory repair systems are
S
systems are produced and installed annually
Summit Photonics
Absorption Contrast is KeyAbsorption Contrast is Key
Professor Schawlow, an early proponent, demonstrates how to employ laser absorption contrast to selectively
S
contrast to selectively process a work piece.
Summit Photonics
1 1 µµµµµµµµm Compared to 1.3 m Compared to 1.3 µµµµµµµµmmAluminum Links
S
1047 nm: Energy level just below damage threshold
1343 nm: Energy level centered in the process
window
Summit Photonics
Picosecond pulse and Thresholding
S
Thresholding on Si substrate
0.90µJ 0.92µJ 0.94µJ 0.96µJ
Summit Photonics
ps Laser Link Processing Results
S
57ps IR laser pulse 35ps IR laser pulse
Summit Photonics
TopicsTopics
• Introduction and Source Architectures
• Semiconductor Micromachining
• Memory Processing
• Thin Film Device Microprocessing
SSummit PhotonicsSummit Photonics
• Thin Film Device Microprocessing
• c-Si and Thin Film Solar Cells Processing
• Emerging Technology and Processes
Thin film removal for Flat Panel Displays532nm
• Patterning of ITO on SiN for flat panel displays.
• 532nm, 5µJ, 200kHz, scan speed =3m/s.
SSummit Photonics
TopicsTopics
• Introduction and Source Architectures
• Semiconductor Micromachining
• Memory Processing
• Thin Film Device Microprocessing
SSummit PhotonicsSummit Photonics
• Thin Film Device Microprocessing
• c-Si and Thin Film Solar Cells Processing
• Emerging Technology and Processes
Comparison of ns and Comparison of ns and psps Edge Isolation Edge Isolation laser processinglaser processing
ns-system ps-system
≤16kΩcm² ≥24kΩcm²
Thermal regime Optical regime
6.6kΩcm²
S
•Results:
•higher shunt resistances
•1 s laser processing time
•less damages
Summit Photonics
psps Edge Edge Isolation of cIsolation of c--Si PV cellsSi PV cells
0,2
0,3
0,4
thermal penetration zone
0.2
0.3
Av.
ab
latio
n d
ep
th p
er
pu
lse
aP (
µm
/pu
lse
)TruMicro 5050
λ = 515 nm
τP = 7.3 ps
fP = 100kHz
0.4
S
0,1 1 10
0,0
0,1
1010.1
0.0
0.1
Av.
ab
latio
n d
ep
th p
er
pu
lse
a
Laser fluence HP (J/cm
2)
optical penetration zone
Htrans
= 1 to 1.1 J/cm2
Typical ablation behaviour for a ps-laser
Summit Photonics
532 nm 532 nm psps MOFPA ablation of MOFPA ablation of SiNSiN on con c--SiSi
SSummit PhotonicsSummit Photonics
Speed: 4000 mm/sAblation threshold ~0.1 J/cm2
Goal: Remove SiN to produce metallization “streets”
532nm
Thin film removal – solar cells
355nmFluence ~0.11 J/cm2
(~1.5 times laser ablation threshold)
532nmFluence ~0.27 J/cm2
(~2 times laser ablation threshold)
355nm
• Selective removal of SiO2 from silicon.
S
• No melt visible when using 355nm close to the laser ablation threshold.
• Some melt is visible on the silicon when using 532nm (note higher fluence).
SEM images courtesy of Nanogram
Summit Photonics
Monolithic interconnection in CIGS solar modules
ZnO:Al Front contact
deposition by
sputtering
Mo back contact
deposition by sputtering
Scribing of Mo
by laser beam
CIGS absorber deposition
by vacuum evaporation
CdS or ZnS buffer
deposition
by chemical method
Patterning of buffer/CIGS
by laser scribing
S
ZnO:Al (1 µm)
CdS or Zns (0.03 µm)
CIGS (2 µm)Mo (1 µm)
Substrate
Patterning of front contact
& wiring
Summit Photonics
CIS P1 CIS P1 by by psps ablationablation, low overlap, low overlap
S
• Ps-front side and ps back side ablation
• Process speed of 2 to 20 m/s possible
• Galvanic separation perfect
• Groove width of ca. 30 µm, depth 400 nm
• No damage on the ablation ground barrier layer functional
Summit Photonics
CIS P3 CIS P3 by by psps ablationablation
S
• Process speed 2 m/s possible
• Groove depth of 3.6 µm Complete separation of the ZnO-CIS-film.
• ZnO-layer (green) is chipped-off without thermal influence and micro cracks,
CIS-film (turquoise) exhibits faint rims on both sides of the groove, Mo-
surface (blue) is free of CIS
• Functionality has still to be validated
Summit Photonics
Laser Shipment Projections for Thin Film Scribers Laser Shipment Projections for Thin Film Scribers
3000
4000
5000
6000L
asers
SSummit PhotonicsSummit Photonics
0
1000
2000
2008 2009 2010 2011 2012 2013 2014 2015
Lasers
Year
Key Assumption: 0.25 Lasers/MW
TopicsTopics
• Introduction and Source Architectures
• Semiconductor Micromachining
• Memory Processing
• Thin Film Device Microprocessing
SSummit PhotonicsSummit Photonics
• Thin Film Device Microprocessing
• c-Si and Thin Film Solar Cells Processing
• Emerging Technology and Processes
Laser Processing of Nontransparent MaterialsLaser Processing of Nontransparent Materials
SSummit PhotonicsSummit Photonics
Laser Processing of Nontransparent MaterialsLaser Processing of Nontransparent Materials
SSummit PhotonicsSummit Photonics
Optical Optical HyperdopingHyperdopingResponsivityResponsivity
SSummit PhotonicsSummit Photonics
LIPSS Processing of Stainless SteelLIPSS Processing of Stainless Steel
SSummit PhotonicsSummit Photonics
Silicon scribing and LIPSS texturing
S
11 µm width groove – depth 6µm
Single Groove
6,5µm deep
Parrallelgrooves
Crossed
grooves
Summit Photonics
Silicon Texturing (black silicon)
Flexible Flexible PulsewidthPulsewidth psps fiberfiber oscillatoroscillator
Narrow spectrum: < 1 nm
Linearly polarized
1064 nm central wavelength
S
Adjustable pulse duration: 30 ps < ττττ < 300 ps
Repetition rate: > 5 MHz
Oscillator output pulse energy: 1-10 nJ.
US Patent application No 12/498,072
Amplification Amplification limitslimits of of psps pulses in pulses in silicasilica fibersfibers @ 1064 nm@ 1064 nm
SRS Maximum peak power SPM Spectral broadening
15
20
Am
plit
ude
nois
e (
± %
)
Amplitude noise on the optical pulses as a function of their peakpower normalized to the effective area of the amplifying fiber
140 ps
70 ps
35 ps
2
3.5
4
4.5
5
sp
ectr
al w
idth
FW
HM
(n
m)
Spectral broadening of the pulse as a function of their peakpower normalized to the effective area of the fiber
140 ps
70 ps
35 ps
S4444
0 10 20 30 40 50 60 700
5
10
Normalized peak power (kW / 100 µm2)
Am
plit
ude
nois
e (
± %
)
40 kW / 100 µm2 of effective area
0 10 20 30 40 50 60 70 800
0.5
1
1.5
2
2.5
3
Normalized peak power (kW / 100 µm2)
sp
ectr
al w
idth
FW
HM
(n
m)
[ ][ ]
[ ] [ ]2300
mApst
kWPnm
effFWHM
peak
FWHMµ
λ∆
≈∆
Summit is a provider of Summit is a provider of Photonics Engineering Services Photonics Engineering Services
• Founded June, 2008
• Office and lab facility in Portland metro area
• Laser processing system architecture design and system selection and evaluation
• Laser source evaluation, design, and selection
S
• Laser source evaluation, design, and selection
• Advanced laser process development and evaluations
• Photonics intellectual property evaluation and creation– IP rights assignment
• Photonics “gap” engineering solutions
Summit Photonics Summit Photonics
Summit Laser Application LabSummit Laser Application Lab
SSummit PhotonicsSummit Photonics
Summary and OutlookSummary and Outlook
• Industrial picosecond laser processes are being
adopted for semiconductor and solar cell
manufacturing.
• LIPSS applications represent an important area
of research and emerging industrial applications.
• High pulse energy applications will continue to
S
• High pulse energy applications will continue to
be dominated by ps laser solutions employing
solid state power amplifiers.
• All fiber ps lasers will compete successfully in the
thin film (PV and display) and semiconductor IC
markets.
Summit Photonics
AcknowledgementsAcknowledgements• Bob Hainsey (ESI)
• Sean Peng (ESI)
• Jeff Albelo (ESI)
• Joohan Lee (GSI)
• Kurt Weingarten (TBP)
• Mark Keirstead (Coherent)
• Pascal Deladurantaye (INO)
• Yves Taillon (INO)
• Maik Frede (LZH)
• Dietmar Kracht (LZH)
• Viktor Schuetz (LZH)
S
• Mark Keirstead (Coherent)
• Colin Moorhouse (Coherent)
• Robert Braunschweig (A-S)
• John Clowes (Fianium)
• Heinz Huber (HiQ)
• Uwe Stute (Trumpf)
• Peter Herman (U. Toronto)
• Ralf Knappe (Lumera)
• Dirk Muller (Lumera)
Summit Photonics
Thank You!
S
Questions?
Summit Photonics