Cession6-Multiple FA techniques on advanced technologies v1...Knowledge for a failure analysis...
Transcript of Cession6-Multiple FA techniques on advanced technologies v1...Knowledge for a failure analysis...
EUFANET Workshop 2009
Cession 6 - Multiple FA techniques on advanced technologies
Sylvain DUDIT
EUFANET Workshop 2009 2
Summary
• Typical EFA flow
• Application on case of analysis
• Focus to put in place for a complex case of analysi s – Optical techniques for fault research and localizat ion– The FIB and AFM-P during the analysis– Knowledge for a failure analyst
EUFANET Workshop 2009 3
Summary
• Typical EFA flow
• Application on case of analysis
• Focus to put in place for a complex case of analysi s – Optical techniques for fault research and localizat ion– The FIB and AFM-P during the analysis– Knowledge for a failure analyst
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Typical EFA flow
Setup after preparation
Electrical setup
Frontsidepreparation
Backside preparation
FA_report
TRE
E-beam
SLS / DLS
EMMI
…
Depro-cessing
Physical analysis
RequestDocumentationsInformations
Defect reproduction
Sample preparation
Fail alwaysAfter
Sample prep
Fault research&
Localization
Sample Preparation
ForPhysical analysis
Physical analysis
Report
FA request
0.2 to 0.5 0.2 to 3 0.2 to 2 0.1 to 0.5 0.2 to 6 0.2 to 2 0.2 to 3 0.2 to 1
Best case: 1.5 Days
Worst case: 18 Days
Interaction with designer /Techno / Test neededDay time
AFM Prob
FIB
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• Typical EFA flow
• Application on case of analysis
• Focus to put in place for a complex case of analysi s – Optical techniques for fault research and localizat ion– The FIB and AFM-P during the analysis– Knowledge for a failure analyst
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Case of analysis (1/5)
• Analysis– Test chip analog and digital on 65nm technology– Fail on specific structure to track the problem @ metallization level– Output stuck @ - no evident over consumption observed
IN OUT
• For a failure analysis point of view– Case with no over consumption : Open, bridge, serial defects– Case with over consumption : short to GND, short to VDD,
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Case of analysis (2/5)
IN OUT
• Dynamic EMMI :– Transistor commutations– High EMMI spot (drawbacks for the low emitter)– No functionality after high EMMI spot– 3 IV impacted by the failure ?
• Next : – Laser stimulation – Goal : best fail understanding
EMMI results
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Case of analysis (3/5)
• Laser Stimulation– SIL220X benefits versus a 100X lenses
• Sensitivity, spatial resolution• Best fail understanding• 2 IV impacted by the failure ? (1 in accordance with EMMI
result)
IN OUT
IN OUT
EMMI results LS results
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IN OUT
IN OUT
EMMI resultsLS results
Case of analysis (4/5)
• TRE results– Not in total accordance with LS
and EMMI– 5 IV impacted by the failure ?
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Case of analysis (5/5)
OUTIN
• Conclusion about fail hypothesis :– Short @ VDD or GND on a very long path– 3 FA techniques of localization with results but without fine localization– DLS technique : Fail (pseudo static fail)
!!! Charge contrast technique use to have the good localization !!!
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• Typical EFA flow
• Application on case of analysis
• Focus to put in place for a complex case of analysi s – Optical techniques for fault research and localizat ion– The FIB and AFM-P during the analysis– Knowledge for a failure analyst
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Fault research & Localization
TLS – Obirch(Tiva)
EMMIstatic
EMMI + SLS
Top & Back sideTop side
- ESD - Hot carriers- Latch-up
PLS – Obic(Liva)
- Floating node- Non bias junction- Resistive path
EBT-Ebeam Tester
Top & Back side
Measurement :- Delay- Rise/fall time@ebeam probe point
TRE
Back side
Measurement :- Delay@transistor level
Dynamic faulttracking:- cross talk- Latch-up
EMMI + Laser tester
SDLEMMIDynamic
Back side
Timing analysisTester
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AFM Probing
Fault research & Localization
Electrical characterization by “in situ”contact
FIB
Front side modification
Backside modification
Cross-section
Ebeam Probe Pad Generation Charge
contrast
Current leakage mapping
Id/VdFAIL
Id/VdREF
60µA
15µA
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Knowledge for a failure analysis
Knowledge needed :
- Sample Preparation ( // polishing, chemical, micro drill …)- Electrical setup ( Power supplies , DC)- CAD navigation setup – Layout view- Optic Tester ( EMMI+SLS) (collaboration with the designers)
- Mechanical deprocessing- Chemical deprocessing- SEM Imaging- Fib editing (F / B) and X-sectioning
Knowledge needed :
- Sample Preparation ( // polishing, chemical, micro drill …)- Electrical setup ( Power supplies , DC)- Electrical setup AC :
°Pattern conversion & Optimization - CAD navigation setup
° Layout view°Netlist view°Schematic view
- Optic Tester 5 ( EMMI+ SLS + TRE + DLS)- E-beam- Comparison with simulation results (close collaboration with the designers)
- AFM probing- Mechanical deprocessing- Chemical deprocessing- SEM Imaging- Fib editing ( F / B) and X-sectioning