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TED DangelmayerPresident & CEO
www.dangelmayer.com
Perfect ESD Storm!CDM & Class 0 Converge in Backend
Copyright © 2007 Dangelmayer Associates 2
Outline
• Introduction• CDM Overview• Lessons from the recent past• Industry Class 0 Trend
– It is Real This Time!
• Backend CDM Issues• CDM & Class 0 Countermeasures• Conclusions
Copyright © 2007 Dangelmayer Associates 3
CDM + Class 0 Trend =
!”The Perfect ESD Storm“
Class 0 – Rapidly Growing TrendCDM Technology not Understood by Most Co’s
CDM = 95% of ESD Failures
Copyright © 2007 Dangelmayer Associates 5
Human Body Model Charged Device Model
CDM and related metal-metal discharge events cause 95% of current ESD problems. This will continue to be the underlying driver for ESD control.
Emergence of CDM ESD (90% to 95% of ESD Failures Today)
Tweezer VideoCDM Video
Copyright © 2007 Dangelmayer Associates 9
Wafer ESD Model Schematic
Field plate at V
Arc model, I(t)- Includes inductance
Small features Large bus
Bulk resistance
V(t)
surface resistance
small cap large cap
neglected
neglected
Wafers Will Experience ESD Damage with Technology Trend!
Copyright © 2007 Dangelmayer Associates 10
Wafer Saw Example
• CDM Threshold – 35 Volts• 92.2% Defective at Wafer Saw• Failure Analysis
– CDM Damage
Copyright © 2007 Dangelmayer Associates 11
Class 0 Case StudyCorresponding Yield Improvements
O v erall E S D Y ield Loss Im prov em ents
0
5
10
15
20
25
1 5 9 13 17 21 25 29 33 37 41 45 49 1 5 9 13 17 21 25 29
W e e k
ESD
Yie
ld L
oss
(%)
Sy c orax
Caliban
Cordelia
T10000A
Consultant Hired
80% EPM Performance Scale™
22% Yield Loss
Out of Control
Copyright © 2007 Dangelmayer Associates 14
Typical IC With Protection Circuitry
Functional Circuitry
Protection CircuitsProtection Circuits Constrained or Omitted By:
•Technology Node Feature Sizes
•Circuit Functionality
•I/O Density
•Speed
Copyright © 2007 Dangelmayer Associates 15
2003 ITRSA recent SEMATECH benchmarking study of integrated
circuit suppliers indicated that ESD will be one of the top three reliability concerns within the next 5 years and already is with
certain products!
Copyright © 2007 Dangelmayer Associates 16
ESD Threshold Populations including high speed applications
ESD Populations including high speed applications
00.00010.00020.0003
0.00040.00050.00060.0007
0 1000 2000 3000 4000 5000 6000
ESD Threshold (volts)
Rel
ativ
e Fr
eque
ncy 1996
20022008HS 1996HS 2002HS 2008
Distribution becoming bimodal
Copyright © 2007 Dangelmayer Associates 17
Class 0 Devices per Factory
Class 0 Devices per Factory
0
0.10.2
0.3
0.4
0.50.6
0.7
1980 1985 1990 1995 2000 2005 2010
Year
#Cla
ss0/
Fact
ory
Class 0:
Virtually all Factories by 2010
Copyright © 2007 Dangelmayer Associates 18
0
500
1000
1500
2000
2500
1980 1985 1990 1995 2000 2005 2010
H B MC D MM M
ESDA Technology Roadmap
(IC Chip Design Experts: “With Our Best Effort”)
Volts
HBM
CDM
MM
IBM; TI; Intel – Ph.D. Chip Design Experts
400 chip design patents
Copyright © 2007 Dangelmayer Associates 19
Sources of Trend Confirmation• ESD Association Roadmap
• SEMETECH – ITRI Roadmap
• DA Customer Reports / Literature Analysis
• ESD Stress Test Labs
• Stress Test Equipment Manufacturers
• IC Mfg/Design: Intel; TI; IBM; AMD etc.– Lowering 2000 volts HBM to 1000 volts
• FA Labs
• Subcontractors – Foxconn; Jabil; Solectron etc.
• OEM’s – Cisco, Nokia, etc.
Copyright © 2007 Dangelmayer Associates 24
No ESD Events Detected!
ESD Events Detected!Bonding Tip Not Grounded!
Bonding Tip Properly Grounded!
Event Video
Copyright © 2007 Dangelmayer Associates 29
ESDA S20.20 Scope: HBM >100V
Note:Tailoring is Essential for Class 0 & CDM
Best Industry
Standard
Copyright © 2003 Dangelmayer Associates 30
MR Head Lessons Learned• Conventional ESD Methods Did Not Work!
– Below 100 Volts– Ionization Too Slow– Incomplete Coverage with Ionization
• Expect a Paradigm Shift @ 100 volts– Assume Device Still Charged!
• New Control Methods– Eliminate Metal-to-Metal Contact– Substitute “Soft Landings” with Dissipative Materials
Copyright © 2007 Dangelmayer Associates 32
ConclusionsCDM + Class 0 Trend = Perfect ESD Storm!
Trend Drivers:• Class 0:
– Virtually All Factories By 2010!– It Takes Two Year To Prepare
• Trends Driven By – Exploding Consumer Markets – High Volume Production
• Designed-in Protection Circuits Limited– By Speed Of Application And I/O Density
Impact On Control Procedures:• Standard Control Procedures
– Insufficient But Necessary• Paradigm Shift In Control Techniques
– Occurs At 100 Volts– Must Assume Product Is Still Charged– Ionization Often Not Sufficient
• Metal-to-metal Contact Must Be Eliminated• EMI/ESD Event Testing Is Essential
Copyright © 2007 Dangelmayer Associates 33
Class 0 - Are You Ready?It Takes 2 Years!
ConsultOr developExpertise
IdentifyChampionAnd Team Detailed
TechnicalAssessment
SchedulingSurvey, Report
By Site
LocateOr DevelopSuppliers
Initiate -> Assess -> Design -> Develop -> Implement
6 months 2-4 months 4-12 months Total time up to 2 years
Develop andDocumentProcedures
TrainEngineers
TrainWorkers
TrainManagers
Purchase Cycle Time
ImplementAnd
Sustain
Purchase Cycle Time
TrainTeam
4-8 weeks per item
By Tool
Tool
Solutions
By Product
Product
Solutions
HS1203