serma technologies reliability method april 2011 · serma technologies reliability method ... bus...
TRANSCRIPT
Serma Technologies Reliability Method APRIL 2011
The classical bath curve…
Usual reliability view
Défauts aléatoires
Random failure
Failure Rate
time
Défauts de jeunesse
Early fails
Fin de vie
Wear out
1 Decrease early fails rate
Usual Tools
Adapted Qualification Process
Process management
Efficient manufacturing test
Adapted Screening
Usual reliability view
Random failure
Failure rate
time
2 Decrease random failure rate
Early fails Wear out
ONE AIM REDUCE THE SENSIBILITY OF THE PRODUCT TO NO-QUALITY PEAKS
The classical bath curve…
Usual Tools
Component quality management
Process management (control & repetitivity)
Permanent improvement of the product
Adapted evolutive Screening / sampling?
3 Is wear out a fear?
Usual reliability view
Random failure
Failure rate
Time
Early fails Wear out
Life duration of the
product
The classical bath curve…
Usual Tools
Reliability tests (durability tests)
Permanent control of the “really aged”
product from the field
Maintenability
5
ARGP ADAPTED RELIABILITY GROWTH PLAN
ADPATED RELIABILITY GROWTH PLAN DEFINITION
RELIABILITY GROWTH PLAN
Qualification Robustness Durability Process
Failure
Mechanism
Technologies
BOM Analyses Design
Design for
Manufacturing
SYNTHESIS OF THE RISKS : A RISK IS LINKED TO A
TECHNICAL ISSUE COMING FROM THESE 4 FIELDS
MISSION PROFILE ANALYSIS
AND
LESSONS LEARNT SYHTESIS
RISK
ANALYSIS
MITIGATION
PLAN
Stress
Probability
Stress level
Resistance
Potential failure
Reliability overview
How decrease this failure rate
probability?
Improve the
robustness and the
durability
Decrease the variability
Screen weakest parts
Reliability growth by product improvment
Improve the robustness and the durability
Stress
Probability
Stress level
Resistance
Potential failure
Improve the robustness and the durability
Stress
Probability
Stress level
Resistance
Potential failure
10
ARGP ADAPTED RELIABILITY GROWTH PLAN
ADPATED RELIABILITY GROWTH PLAN DEFINITION
RELIABILITY GROWTH PLAN
Qualification Robustness Durability Process
SYNTHESIS OF THE RISKS : A RISK IS LINKED TO A
TECHNICAL ISSUE COMING FROM THESE 4 FIELDS
Failure
Mechanism
Technologies
BOM Analyses Design
Design for
Manufacturing
MISSION PROFILE ANALYSIS
AND
LESSONS LEARNT SYHTESIS
RISK
ANALYSIS
MITIGATION
PLAN
11
Profil de mission
Détermination du profil de mission des utilisateurs finaux et du profil industriel
(depuis l’approvisionnement jusqu'à la livraison du produit)
ENVIRONNEMENT
UTILISATEUR
Grandeurs
Physiques
Thermique
Mécanique
Electrique
Chimique
Radiatif
...
OBJECTIFS
FIABILITE
CONDITIONS
UTILISATIONS
Grandeurs
Physiques
Questionnaire
Support Techn.
Durée de vie
Taux de défaillance
Conditions de fct
Maintenabilité
Sécurité
...
ENVIRONNEMENT
INDUSTRIEL
Questionnaire
Support Techn
Description du
processus
industriel
ESD
Chocs T° et Humidité
type de brasage
profil de brasage
...
12
ARGP ADAPTED RELIABILITY GROWTH PLAN
ADPATED RELIABILITY GROWTH PLAN DEFINITION
RELIABILITY GROWTH PLAN
Qualification Robustness Durability Process
Failure
Mechanism
Technologies
BOM Analyses Design
Design for
Manufacturing
SYNTHESIS OF THE RISKS : A RISK IS LINKED TO A
TECHNICAL ISSUE COMING FROM THESE 4 FIELDS
MISSION PROFILE ANALYSIS
AND
LESSONS LEARNT SYHTESIS
RISK
ANALYSIS
MITIGATION
PLAN
BOM ANALYSES
Objective verify the “good” (or less risky?) choice of
component
Why ? designer is sometimes alone for this important
and technological choice
How by verifying each line of the BOM with different
parameters defined with the project team :
References Obsolete
Temperature specification Technology
Qualification Plating
ESD MSL level
BOM ANALYSES
Each line of the BOM is analyzed versus criteria defined
depending on the project MSL, temperature
specification, qualification, technology, obsolete status,…
15
ARGP ADAPTED RELIABILITY GROWTH PLAN
ADPATED RELIABILITY GROWTH PLAN DEFINITION
RELIABILITY GROWTH PLAN
Qualification Robustness Durability Process
Failure
Mechanism
Technologies
BOM Analyses Design
Design for
Manufacturing
SYNTHESIS OF THE RISKS : A RISK IS LINKED TO A
TECHNICAL ISSUE COMING FROM THESE 4 FIELDS
MISSION PROFILE ANALYSIS
AND
LESSONS LEARNT SYHTESIS
RISK
ANALYSIS
FAILURE MECHANISMS
Famille technologique Principaux mécanismes de défaillance Commentaire vs profil de vie
Condensateur
céramique
multicouche,
cms
Vide entre couches, mauvaise qualité des
terminaisons …
Possible en cas de choix de source non qualifiée
Possible en cas de choix de composants en limite
de gamme
Fissure de la céramique induite par un stress
mécanique et courant de fuite entre les couches
internes, en présence d’humidité et de tension,
entraînant une dérive des valeurs ou un court
circuit
Stress mécanique possible lors des phases process
Humidité et tension présentes en utilisation
Courant du fuite ou migration dendritique
entre les électrodes en présence de résidus,
humidité et tension
Résidus issus du process (flux, particules diverses,
trace de doigt…)
Humidité et tension présentes en utilisation
Réduction dans le temps de 10 à 20% de la
capacité (Y5V et X7R) ; phénomène annulé lors
des phases on/off
Possible car produit 100% du temps sous tension
Dérive des paramètres en température (Y5V) Possible ponctuellement (si composant près d’un
point chaud et température ambiante extrême…)
Component by component, listing of the well know failure
mechanisms (state of the art, company experience,
lessons learnt) and proposal of preventive actions
17
ARGP ADAPTED RELIABILITY GROWTH PLAN
ADPATED RELIABILITY GROWTH PLAN DEFINITION
RELIABILITY GROWTH PLAN
Qualification Robustness Durability Process
Failure
Mechanism
Technologies
BOM Analyses Design
Design for
Manufacturing
SYNTHESIS OF THE RISKS : A RISK IS LINKED TO A
TECHNICAL ISSUE COMING FROM THESE 4 FIELDS
MISSION PROFILE ANALYSIS
AND
LESSONS LEARNT SYHTESIS
RISK
ANALYSIS
DESIGN with PRODUCT FMEA
Bus CAN Moteur
Capteur
Alimentation Température
Calculateur
…
Analyse
fonctionnelle
Grille d’analyse
-Mise à jour / ajout de précisions dans les spécifications produit
-Ajout d’actions de vérification (revue de conception, spécification
composant, analyse de risque composant, AMDEC composants…)
-Amélioration du plan de validation (ajout d’essais, sévèrisation…)
-Implémentation d’essais de robustesse / vieillissement accéléré
-Alimentation des plans de surveillance process (paramètres critiques)
-Etc.
Exemples d’actions
correctives
DESIGN par le biais d’AMDEC composant
L’objectif est d’analyser en détail les dysfonctionnements des sous ensembles critiques et d’évaluer quantitativement leur probabilité d’occurrence
L’approche est matérielle (analyse des schémas) et nécessite l’utilisation d’un recueil de fiabilité pour l’analyse de criticité
Grille d’analyse Exemples d’actions
correctives
•Amélioration design (positionnement /combinaison des
composants ; dérating)
•Choix de composants plus sûr (capacité céramique à structure
série)
•Choix de composants plus fiables
•Mise en place de mécanismes de détection de panne
•Rebouclage avec d’autres analyses de sûreté (Arbres de
défaillances)
•Implémentation de tests périodiques (maintenance)
• Etc.
20
ARGP ADAPTED RELIABILITY GROWTH PLAN
ADPATED RELIABILITY GROWTH PLAN DEFINITION
RELIABILITY GROWTH PLAN
Qualification Robustness Durability Process
Failure
Mechanism
Technologies
BOM Analyses Design
Design for
Manufacturing
SYNTHESIS OF THE RISKS : A RISK IS LINKED TO A
TECHNICAL ISSUE COMING FROM THESE 4 FIELDS
MISSION PROFILE ANALYSIS
AND
LESSONS LEARNT SYHTESIS
MITIGATION
PLAN
Pre test
Assessment
Conception Validation
Robustness
Reliability
Growth
Plan
Qualification
Qualification Test Plan
Manufacturing
Screening
Life
Lessons learnt
QUALIFICATION OVERVIEW (Board & system)
Number of parts available
Standard Robustness Durability Other
Railways EN50155, …
No No
Functional validation
and safety / availability
are primordial
Automotive
No worldwide standard
but specific to car
manufacturer (Renault,
PSA,…)
Punctual Yes
Robustness is
becoming more and
more a requirement
Aeronautic DO160 No No
Robustness is required
but out of the scope of
the qualification
document
Industrial
IEC are available but
not gathered in a
global approach
No No
Reliability and
robustness are put in
place for new important
development
Samples Generally 1 to 5 samples by individual test
QUALIFICATION OVERVIEW (Board & system)
Some suppliers use « reliability method » for life duration assessment but many equipments
are used with low qualification. Functional validation is only performed (performance)
QUALIFICATION OVERVIEW (Board & system)
QUALIFICATION OVERVIEW (Board & system)
Process Qualification
Supplier
qualification
Risk analysis
(PFMEA…)
Design Qualification
Risk analysis (DFMEA…) Robustness
Manufacturing qualification
Variability Follow-up
PCQM
QUALIFICATION OVERVIEW
Technology Qualification PERMANENT RESEARCH
Lead free Press fit Conductive polymer Planar PCB
Component Qualification
PPAP CA Reliability Tests
Supplier audit Robustness Tests
Product Qualification
Reliability Robustness
QTP
QUALIFICATION OVERVIEW
Process Qualification
Supplier
qualification
Risk analysis
(PFMEA…)
Design Qualification
Risk analysis (DFMEA…) Robustness
Manufacturing qualification
Variability Follow-up
PCQM
Technology Qualification PERMANENT RESEARCH
Lead free Press fit Conductive polymer Planar PCB
Component Qualification
PPAP CA Reliability Tests
Supplier audit Robustness Tests
Product Qualification
Reliability Robustness
QTP
Process Qualification
Supplier qualification
Risk analysis (PFMEA…)
Design Qualification
Risk analysis (DFMEA…) Robustness
Manufacturing qualification
Variability Follow-up
PCQM
RELIABILITY MANAGEMENT
QUALIFICATION OVERVIEW
Technology Qualification
Lead free Press fit Conductive polymer Planar PCB
Component Qualification
PPAP CA Reliability Tests
Supplier audit Robustness Tests
Product Qualification
Reliability Robustness
QTP
HTOL T&H Thermal
cycling Vibration
Railways Some hours
T max
Some hours
55°C / 85%RH
+ dew
Specific Critical frequency research +
dependant to application
Automotive X 000 h
95/125°C
> 500 h
85°C/85%RH
> 1 000 cycles
Tmin >160°C
Resonance up to 1kHz (1g)
Sine(powertrain) 1kHz (10g)
Random 1kHz
Shocks up to 100g 6ms
Aeronautic Some hours
Tmaxspec
> 200 h
65°C/95%RH
Some cycles
T 160°C
Yes but dependant to
application
Comments -
Generally low
humidity in
use
- -
QUALIFICATION OVERVIEW (Board & system)
29
ARGP ADVANCED RELIABILITY GROWTH PLAN
Failure
Mechanism
Technologies
BOM Analyses Design
Design for
Manufacturing
SYNTHESIS OF THE RISKS : A RISK IS LINKED TO A
TECHNICAL ISSUE COMING FROM THESE 4 FIELDS
ADPATED RELIABILITY GROWTH PLAN DEFINITION
RELIABILITY GROWTH PLAN
Qualification Robustness Durability Process
MISSION PROFILE
AND
LESSONS LEARNT ANALYSIS
Principle
Increase the stress progressively (by step)
Go over mission profile / specification values
Identify weaknesses of the product
Measure functional or destructive margins
Stress
T°, DT, V, I , P ….
Mission profile
Specification
Operating limit
Destruct limit
TEST
Why the robustness ?
Why the robustness ?
Stress HIGH
TEMPERATURE
(°C)
Stress BIAS
(V)
Stress HUMIDITY
Stress
VIBRATION /
SHOCKS
(G rms)
Stress THERMAL
CYCLING (°C/mn)
Usual
qualification?
Why the robustness ?
Stress HIGH
TEMPERATURE
(°C)
Stress BIAS
(V)
Stress HUMIDITY
Stress
VIBRATION /
SHOCKS
(G rms)
Stress THERMAL
CYCLING (°C/mn)
PROSPECTING OF THIS AREA
Stress
T°, DT, V, I , P ….
Results discussion
- Failure mode analysis Action ?
- Operating limit ?
- What about quality dispersion?
MARGIN
Mission profile
Specification
Operating limit
Destruct limit
Stress
T°, DT, V, I , P ….
Results discussion
- Failure mode analysis action ?
- Destruct margin ?
MARGIN
Mission profile
Specification
Operating limit
Destruct limit
– System analysis (Technolgical limit, thermal limitation,…)
– Technological risk analysis (what could be the weaknesses?)
– Stress choice (linked to technologies, to mission profile
or…to nothing? PROSPECTING ?)
– Tests choice
– Fixation study
– Monitoring study
– Implementation of the tests
– Results analysis and improvement
– Screening definition ?
The different steps of the method
36
ARGP ADVANCED RELIABILITY GROWTH PLAN
Failure
Mechanism
Technologies
BOM Analyses Design
Design for
Manufacturing
SYNTHESIS OF THE RISKS : A RISK IS LINKED TO A
TECHNICAL ISSUE COMING FROM THESE 4 FIELDS
ADPATED RELIABILITY GROWTH PLAN DEFINITION
RELIABILITY GROWTH PLAN
Qualification Robustness Durability Process
MISSION PROFILE
AND
LESSONS LEARNT ANALYSIS
Défauts aléatoires
Random failure
Taux de défaillance
temps
Défauts de jeunesse Early fails
Fin de vie
Wear out
Durée de vie ciblée
Is the life duration sufficient?
Durability
38
Méthodes principales
• MIL-HDBK217 ()
• RDF2000 du CNET - UTE 80810 / septembre 2000 / CEI 62 380
• FIDES
• ….
Principe
• Recueil de fiabilité basée sur le retour d ’expérience
• Somme des taux de défaillance des composants, de leurs connexions et du
support (PCB)
Inconvénients
• Résultats pessimistes / hypothèses de calcul (quelques contraintes)
• Mises à jour non récentes
• Pas de prise en compte du process
Les méthodes théoriques
39
Principe
Collecter et analyser toutes les défaillances apparues en
clientèle ( + intégration système & assemblage carte…)
Avantage
Meilleure évaluation du niveau de fiabilité
Inconvénients
• Mode réactif et non préventif
• Logistique pour la collecte des informations
• Pertinence des informations recueillies ( durée d’utilisation,
contexte de la défaillance, quantité de pièces en service,
« pollution » des résultats par la maintenance système, …)
• Fiabilité prévisionnelle ?
Retour d’expérience REX
40
Analyse / définition
Du profil de vie
Analyse de risques
(FMEA, composants, Process, …)
Construction et réalisation du plan
de levée de risques
Analyses et synthèse des résultats
+ Déverminage + définition
Politique d’assurance qualité
composant + actions process
• Axe « Qualification » (performances)
• Axe « Robustesse » (contraintes)
• Axe « Durabilité » (vieillissement)
• Axe « Process » (variabilité)
L’ approche Serma Technologies
41
Durabilité
et essais de vieillissement
Principe :
• Identification des modes de défaillance
• Modélisation des facteurs d’accélération
• Définition et réalisation des essais
BUT :
Provoquer des pannes potentielles dans un temps plus court que le temps d ’utilisation
Les mécanismes de défaillances sont accélérés par :
La température
La variation de température
La tension / le courant / la puissance
L ’humidité associée à la température
Durabilité
Accelerated ageing tests
Examples of failures mechanisms
Conditions
Load Life, High Temperature Operating Life
(Arrhénius)
oxyde defect, ionic contamination, electromigration, interface degradation (current density) card dysfunction because of electrical parameter drift at component level
Temperature from 50°C to 125 °C Duration depends on mission profile Polarization System powered with dynamic electrical stimulations same as use
Baking (storage) at high Temperature
(Arrhénius)
Oxide breakdown, intermetallic growth Data retention, …
Cycles/ Thermal shocks
(Coffin-Manson)
thermo-mechanical fatigue, cracks / delamination / degradation interfaces, solder joints, plastic packages, ceramic capacitor …
Temperature from –55°C to +150°C Gradient from some °C /min to x * 10 °C/min Polarization many times without power
Temperature & Humidity PCT / HAST
(Peck-Bell Lab)
Corrosion die, substrate, pins, card, housing Metallic Migration between polarized lines (component / card)
Humidity from 60% to 95 % HR Temperature from 40°C to 95°C Duration depends on mission profile Polarization static (no power) Temperature to 130°C Humidity to 100% Pressure to 3 atmosphere
Durability
Example of solder joint ageing on Sn Pb (tin lead) solder (solder coarsening):
Example of
« corrosion »
On PCBA due to
Flux residues
Example of « metallic
migration» on PCBA
Initial state
After 1000 cycles of thermal shocks
-55°C / +125°C (1 cycle / h)
QUESTIONS