AN1231 Motorola / Freescale Semiconductor, AN1231 Datasheet - Page 2

• Manufacturer Part Number: AN1231
• Description: Plastic Ball Grid Array (PBGA)
• Manufacturer: Motorola / Freescale Semiconductor

AN1231
2
physical properties of all the materials that comprise the
PBGA package. It is important to note that the properties of
Table 2 provides nominal room temperature values for the
Copper (ED/Rolled)
62% Sn/36% Pb/2% Ag Solder
Dry Film soldermask
BT/Glass Subtrate
Silicon Die
Mold Compound
Ag Filled Epoxy Die Attach

0.4 – 0.6 mm
BT/GLASS PCB
Material
FR4/GLASS PCB
NOTE:
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Table 2. Physical Properties of All Materials Used in the PBGA Package at 23 C
Soldermask Thickness
Soldermask Opening
Substrate Thickness
Substrate Thickness
Trace/Space Widths
Table 1. Typical Nominal Dimensions of Selected PBGA Substrate Features
Copper Thickness
ADHESIVE DIE ATTACH
Solder Pad Cu
(Four Layer)
(Two Layer)
= Diameter. All dimensions are approximate and are for reference only.
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Feature
Via
Figure 1. Cross-Sectional View of an PBGA Mounted to a PCB
Modulus (ksi)
62Sn/36Pb/2 Ag or 63Sn/37Pb
SOLDER BALL (OR BUMP)
Elastic
17,500
18,900
4,600
2,200
2,300
1,070
580
THERMAL/
GROUND VIAS
14.1/0.36
7.9/0.20
SILICON DIE
Dimension (mil/mm)
0.71/0.018
Poisson’s
17.3/0.44
24.0/0.60
1.2/0.030
3.5/0.090
11.8/0.30
Ratio (--)
2.0/0.05
1.2/0.03
9.8/0.25
33/0.84
31/0.78
25/0.64
23/0.58
0.345
0.195
0.278
0.40
0.25
OR
0.4
0.3
60.0 mil, 1.27 or
1.5 mm PITCH
15.7/0.40
21.9/0.56
many of the PBGA materials have a temperature-depen-
dence that is not included in the table.
Au BOND WIRES
1085 (melt)
1412 (melt)
178 (melt)
( C)
175
196
T g
120
77
Comment
BT/glass laminate core thickness.
Overall (BT/glass + Cu + soldermask).
BT/glass laminate core thickness.
Overall (BT/glass + Cu + soldermask).
Clad to BT/glass laminate.
Plated on (electroless + electrolytic).
Minimum.
Over BT/glass.
Over copper features.
Typical Minimum.
Normal.
Most 1.5 mm/60 mil pitch devices.
Specific 1.27 mm pitch devices.
Most 1.5 mm/60 mil pitch devices.
Specific 1.27 mm pitch devices.
SOLDER PADS
< T g (ppm/ _ C)
CTE – x, y/z
EPOXY OVERMOLD
(OR GLOB–TOP)
13/57
2.6
17
21
35
15
52
ROUTING VIAS
MOTOROLA FAST SRAM
Thermal Cond.
0.8 – 1.2 mm
0.36 – 0.60 mm
(W/m- K)
0.33
0.19
0.67
1.38
418
50
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