ipc part: 3 base material for printed circuit boards a pwb is born and develops into an unruly...
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IPC Part: 3Base Material
for Printed Circuit Boards
A PWB is born and develops into an unruly teenager.
Product spec
Component data
Electronic scheme
Net listBOM
IPC-2141AIPC-2251
IPC-7093
J-STD-609AIPC-1752AIPC-2610
IPC-7094
Footprints
Component placement
Routing
IPC-2222AIPC-7351BIPC-7095CIPC-7525B
IPC-2221B
Program for:-Laser Plotter-Drilling-Routing-AOI-Electric test
IPC-2581
To Bare Board
Production
Gerber filesDrill filesBare BoardSpec
IPC-2152
IPC-7527
FR4FR4
High Tg
FR4 BFR Free
?FR4 IL
IPC-4101D
IPC-4562A IPC-4121IPC-4563
DATA from CAM
IPC-9691A
Please fill in!!
IPC StandardsBase Material Standards.• IPC-4101D Rigid Boards.• IPC-9691A CAF.• IPC-4562A Metal Foil for Board Applications.• IPC-4563 RCC Foil for Board Guideline.• IPC-4121 Guideline for Selecting Core
Construction for Multilayer Applications.
IPC-4101DMaterial Composition Keywords All Appropriate Specification SheetsBT / Epoxy / Woven Glass 30
Cyanate Ester / Woven Aramid 54
Cyanate Ester / Woven Glass 71
Cyanate Ester / Woven S-2 Glass 70
Cyanate Ester / Woven Quartz 61
Epoxy / Cyanate Ester / Woven Glass 29
Epoxy / Non-Epoxy / Nonwoven Aramid 58
Epoxy / Non-Epoxy / Nonwoven Glass 28
Epoxy / Nonwoven Aramid 55
Epoxy / Paper 04
Epoxy / PPO / Woven Glass 25, 103
Epoxy / Woven Aramid 50
Epoxy / Woven Glass 20, 21, 22, 23, 24, 26, 27, 82, 83, 92, 93, 94, 95, 97, 98, 99, 101, 121, 122, 124, 125, 126, 127, 128, 129, 130, 131
IPC-4101DMaterial Composition Keywords All Appropriate Specification SheetsEpoxy / Woven Glass / Nonwoven Glass 12, 16, 81
Epoxy / Woven Glass / Paper 10, 15, 80
Phenolic / Paper 00, 01, 02, 03, 05
Polyester / Glass 13
Polyester / Woven Glass / Nonwoven Glass
11
Polyimide / Epoxy / Woven Glass 42
Polyimide / Nonwoven Aramid 53
Polyimide / Woven Glass 40, 41
Polyimide / Woven Quartz 60
PPE / Woven Glass 90, 91, 96, 102
IPC-4101DDescription or Application
KeywordsAll Appropriate Specification Sheets
Additive / Semi-Additive 80, 81, 82, 83
Composite 10, 11, 12, 14, 15, 16
Consumer Electronics 00, 01, 02, 03, 04, 05, 10, 11, 12, 14, 15, 16, 80, 81, 82, 83
Crossplield Unidirectional 27, 54
Double-Sided 12, 14, 16, 81
Heatsink Application 31, 32, 33
Lead-Free FR-4 99, 101, 121,122, 124, 125, 126, 127, 128, 129, 130, 131
Lead-Free Non-FR-4 16, 102, 103
Microvia 53, 55, 58
RoHS
IPC-4101DANSI or Military Keywords All Appropriate Specification SheetsCEM-1 10, 15, 80
CEM-3 12, 14, 16, 81
CRM-5 11
FR-1 02
FR-2 03, 05
FR-3 04
FR-4 21, 24, 26, 27, 82, 83, 92, 93, 94, 95, 97, 98
FR-5 23
G-10 20
G-11 22
XPC 00
XXXPC 01
GFN 21
GFT 26, 28
GPY 30, 40, 41, 42
IPC-4101DMaterial Property Keywords All Appropriate Specification SheetsCAF Resistance 29, 30, 61, 70, 71, 102, 126, 129, 130, 131
High Td (Decomposition Temp) 99, 124, 125, 126, 128, 129, 130, 131
High Reliability 40, 41, 42
Hot Flex Strength 22, 23
Low Dk / Df 13, 25, 50, 53, 54, 55, 58, 61, 70, 71, 90, 91, 96, 102, 103
Low Halogen Content 05, 14, 15, 58, 92, 93, 94, 95, 96, 122, 125, 127, 128, 130, 131
Low X / Y CTE 50, 53, 54, 55, 58, 60, 61, 70
Low Z-axis CTE 99, 101, 102, 121, 122, 124, 125, 126, 127, 128 129, 130, 131
Non-Flame Retardant 20, 22
Thermally Conductive 31, 32, 33
RoHS
RoHS
RoHS
IPC-4101DMaterial Modifier Keywords All Appropriate Specification SheetsFillers 10, 11, 12, 13, 14, 15, 16, 31, 32, 33, 40, 41, 42,
80, 81, 82, 83, 97, 98, 99, 101, 102, 103, 126, 127, 128, 130
Multifunctional Epoxy 24, 55, 83, 94, 95, 98
RoHS
Early & New Curing Agents• Dicy
– Dicyandiamide.– Cure system for epoxy launched in 1970s.– Replaced ”Novolac” Phenolic cure system .
• The reason was that ”Novolac” miss colored the laminate.
– Used in standard FR-4 base material.
Early & New Curing Agents • Non-Dicy
– The “old” Phenolic (Novolac) cure system.– Reintroduced due to RoHS!– Improves the Thermomechanical parameters for
the laminate: • Higher Tg and Td. • Lower Overall CTE.
– Used in FR-4 base material suitable for Lead Free processes.
RoHS
Early & New Curing Agents• Filler
– Talc [Mg3Si2O10(OH)2]• But can be something else; often proprietary
– Fillers more heavily used due to RoHS!– Improves the Thermomechanical parameters for the
laminate:• Lower overall CTE• Higher Td
– Used in FR-4 base material suitable for Lead Free processes. RoHS
IPC-4101DSpecification for Base Material• Cupper foil thickness. • Thickness tolerances.• Overview Tables.• Specification Sheets for Base Laminates
(66 separate base Materials)
IPC-4101D
Important Parameters for Base Materials
• Tg = Glass transition temperature• Td = Degradation temperature
• T260 = Time to delaminating at 260˚ C
• T288 = Time to delaminating at 288˚ C
• CTE = Coefficient of Thermal Expansion
Tg = Glass Transition Temperature
Movie_02.wmv
24
Glass Transition Temperature Tg ( PCB Laminates)
50˚C
100˚C
150˚C
200˚C
250˚C
300˚C
0˚C
Expans
Ion
P/
P
M
Glass Epoxy Laminate FR4
Tg ~125˚C
280 ppm
< 60 ppm
a1
Z-axis Expansion
Effects of Entrapped Moisture in PCB !!!
a1
TgTg
Tg Reduction from 10 to 30°C depending on PCB material, fabric,Cu %
Warping of PCB and Substrate of P-BGA
Z
25
Since moisture acts as a plasticizer, it reduces the Glass Transition Temperature Tg (- 10 to 30°C), effects on CTEz, which in turn increases stresses on PCB features such as Plated Tthrough-Holes (PTH), and the same for P-BGA substrate (ie. FR4, BT), etc..
PCB Moisture Absorption – Additional issue
Room Temperature
Expansion After Tg
CTE = Coefficient of Thermal Expansion
RoHS
Temp over Tg gives high CTE
CTE Cu = 15 ppm/ºC
CTE FR-4 in z-axis 50-60 ppm/ºC under Tg
CTE FR-4 in z-axis 250-300 ppm/ºC over Tg
SAMPLE A
Influence of CTE
How many PTH do you have in your PCB?
What is the consequence of the Base material in the Reflow process?
What is the Result?
FR4FR4
High Tg
FR4 BFR Free
?FR4 IL
IPC-4101D
IPC-4562A IPC-4121IPC-4563
DATA from CAM
IPC-9691A
CAFConductive Anodic Filament
38
How does it look like in the real world?
Regarding CAF
CAF – Example
Conductive Anodic Filament =
Electrochemical reaction between copper anode and cathode
Formation of copper filaments (Electro migration)
RoHS?
Glass fabrics
Resin
Cu Cu
Bonding zone
Glass fabrics
Resin
Cu Cu
Bonding zone
Humidity is absorbed in the PCB
After some time a humidity layer is formed by time
42
PTH - PTV Walls
Moisture (H2O) and Ionic Impurities - pH
CAF
Anode (+) Cathode (-)
Cu CuFabric Fiber Glass plus Resin
Power DC
H2O
Conductive Anodic Filament CAF
H+ions OH- ions
Bad Drilling, Bad Hole Metallization, PTH Voids, Laminate Blistering, ecc, together with Moisture and DC Power, easy to have CAF Formation
Cu salts
43
Cu Cu
Anode (+) Catode (-)
Fiber Glass CAF
H2O Moisture
DC Power
H+ions OH- ions
CAF Formation and Growing Mechanism
Epoxy resin
Cu salts
44
CAF
+ 20 Volt Power Plane
Component Through Hole
A SEM micrograph illustrating the type of catastrophic failure that can be caused by CAF
45
• Interfacial degradation resin-fiber glass (and
moisture).can result in a reduced Time To Failure (TTF) due to ..Conductive Anodic Filament Formation (CFF) (CAF).
• Demand for laminate and PCB material CAF Resistant is Growing as the Lead Free and HDI Technology has an increased market .
PCB Moisture AbsorptionMoisture can cause :
IPCUser Guide for the
IPC-TM-650• IPC-9691A
– 2.6.25 Conductive Anodic Filament (CAF) Resistance Test (Electrochemical Migration Testing)
FR4FR4
High Tg
FR4 BFR Free
?FR4 IL
IPC-4101D
IPC-4562A IPC-4121IPC-4563
DATA from CAM
IPC-9691A
Practical Advice
You need anIPC Checklist!!
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