Transcript AFM Probing Fundamentals

Submicron Probing Techniques
Based on AFM Technology
Presented By: Dr. Michael Harz &
Dr. Thomas Thärigen
Content
I.
II.
III.
IV.
V.
VI.
Introduction / Motivation
Principle
Set Up
Performance
Applications
Conclusion
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Introduction
Motivation
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Visual location
Probe placement
Challenges
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Time to data
Device damage
Circuit charging
Standard environment
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Content
I.
Introduction / Motivation
II.
Principle
III.
IV.
V.
VI.
Set Up
Performance
Applications
Conclusion
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Principle of AFM Probing
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Basic AFM principle for imaging
Use of the AFM tip to make electrical contact
Lens
GOAL:
Laser
Mirror
Detector
y
x
DUT
3D Piezo
Actuator
Measurement
Unit
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Collect
electrical data
quickly for
Failure
Analysis and
Design
Verification
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Probing Procedure
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Setup standard probe station
Place sample on chuck
Coarse positioning of AFM
ProbeHead(s)
Measurement equipment setup
AFM navigational scan
(38 µmx38 µm)
AFM positional scan (approx.
10 µm x 10 µm)
Probe placement(s)
Measurement
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Content
II.
Introduction / Motivation
Principle
III.
Set Up
I.
IV.
V.
VI.
Performance
Applications
Conclusion
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Complete Submicron Probing Setup
 ProbeHead with AFM Technology
 PC-based controller
 Fits to all SUSS probe stations
 Vibration isolation table required
 Up to 3 probes can be
placed within 1x1µm area
 Easy to use software
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AFP Probehead
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Cartridge & Probe Tip
Intelligent cartridges:
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Application decides type
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Frequencies up to 3 GHz
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Active and passive probes
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Equipped with EEPROM
covering
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Statistics (e.g. lifetime)
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Type
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Calibration data
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Content
III.
Introduction / Motivation
Principle
Set Up
IV.
Performance
I.
II.
V.
VI.
Applications
Conclusion
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Performance: Imaging
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Placement accuracy: R=90 nm
Image resolution: 50 nm
Zoom function
Damage free imaging using constant force scan
12 x 12 µm scan
38 x 38 µm scan
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Performance: Contact Stability
Test Procedure: Resistant Measurement
10 x 60sec contact on aluminum metal wafer
1000sec contact on aluminum metal wafer
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Performance: RF Measurements
“AP3” performance
Response
Rise time
120 ps
(3 Ghz)
@ 10 MOhm
input impedance
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Performance: Active Probe Linearity
Sourcemeter
Multimeter
1,40
50 OHM
1,35
GND
1,30
Pico- resp.
AFMProbe
1,25
Vtip
1,20
SUSS AP3
1,15
1,10
1,05
1,00
Picoprobe 34A
0,95
0,90
-1
-0,2
0,6
1,4
2,2
3
Vsource
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Content
IV.
Introduction / Motivation
Principle
Set Up
Performance
V.
Applications
VI.
Conclusion
I.
II.
III.
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Applications: Surface Submicron Probing
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Metal layers (live part)
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Failure analysis
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Design verification
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Device characterization
 Contact level (dead part)
 Transistor characterization
 Failure analysis
 Design verification
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Applications: Fib – Hole Probing
Probe
placement
Optical image
Bottom of hole
scan
Surface scan
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Application: CAD Navigation
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Software supported Area Of Interest (AOI) search
Basing on CAD chip layout
SUSS PA 200 with Raith CAD
Navigation Software
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Conclusions
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Atomic Force Micro Probing is a useful tool to master the
next generation test challenges.
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Compared to other submicron test technologies AFM Probing
offers the following major advantages:
– Extremely short time to data
– Use under standard environment conditions
– Portable
– Tester independent
– Easy to use
– Usual probing interfaces useable (e.g. CAD Navigation)
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