HDI Microvia Standard
Design Guide
HDI Microvia Standard Design Rules
microvia (for impedance
controlled PCBs)
pad ø 325 µm
final ø 100 μm
stacked microvia
outer layer layout
standard microvia
pad ø 300 μm
final
ø 100 μm
Cu – filled
up to max. 4 layers
dielectric
thickness
58 – 70 μm
pad ø 550 μm
final ø 200 / 250 μm
dielectric
thickness
85 – 110 μm
distance pad / track 100 μm
track width 100 μm
distance track / track 100 μm
dielectric thickness
58 – 70 μm (layer 1-2)
dielectric thickness
55 – 68 μm (layer 2-3)
microvia
aspect ratio = 1 : 0.8
(diameter / depth)
core material 100 μm
core material
prepreg
buried
via
prepreg 100 μm
pth
microvias layer 1 to 3
pitch 400 μm
max. 55 μm
max. 18 μm
max. 50 μm
solder mask clearance 50 - 65 µm
track width 100 / 125 µm
BGA pad ø 350 µm
m
final ø 125 μm
pitch 300 μm
pad ø 350 μm
inner layer clearance ø 550 μm
pad ø 550 μm
inner layer
staggered microvias
distance track / track 100 μm inner layer
final ø 200 / 250 μm
inner layer track width 100 μm
pad ø 550 μm
distance pad / track 100 μm inner layer 0.75 mm pitch
distance pad / pad 100 μm inner layer
inner layer layout (up to 35 μm Cu thickness)
BGA 0.80 mm pitch
BGA 0.75 mm pitch
BGA 0.65 mm pitch
0.65 mm pitch
solder mask
clearance 35 µm
Var. 1: Dogbone with throughhole vias
Var. 2: Dogbone with microvias
solder mask clearance 50 - 65 µm
Var. 1
BGA solder pad
Var. 3: Microvia in pad
Var. 2
Var. 3
max. 400 µm
-
max. 500 µm
Solder mask clearance
50 µm
≥ 50 µm
50 µm
Via pad size BGA area
500 µm
-
-
Microvia pad outer layers
-
300 / 350 µm
300 / 350 µm
Microvia pad inner layers
-
300 / 350 µm
300 / 350 µm
Track width / spacing outer layers
≥ 100 µm
≥ 100 µm
≥ 100 µm
Track width / spacing inner layers
≥ 100 µm
≥ 100 µm
≥ 100 µm
BGA 0.50 mm pitch
solder pad
ø 275 µm
track width 100 / 125 µm
BGA pad ø 350 µm
m
BGA pad ø 350 µm
track width 90 / 100 µm
solder mask clearance 50 µm
0.75 mm pitch
QFP 0.40 mm pitch
BGA 0.40 mm pitch
solder mask web ≥ 70 µm
solder mask
clearance 35 µm
solder mask clearance 62 / 50 µm
solder pad
ø 275 µm
blue = outer layer
green = solder mask
red = layer 2
black = layer 3
violet = layer 4
track width 100 µm
pad ø 300 µm
Var.1: Via in pad
BGA solder pad
Solder mask clearance
Microvia pad outer layers
Microvia pad inner layers
Var. 2: Dogbone
solder pad
microvia pad
on layer 1
Var. 3: Via in pad
0.65 mm pitch
Var. 1
Var. 2
Var. 3
300 - 330 µm
240 µm
275 µm
50 µm
40 µm
35 µm
≥ 300 µm
275 µm
275 µm
275 µm
275 µm
275 µm
Track width / spacing outer layers
≥ 100 µm
80 / 90 µm
75 µm
Track width / spacing inner layers
75 µm
75 µm
75 µm
microvia pad
ø 300 µm
on layer 2
microvia pad
ø 300 µm
on layer 3
solder pad 200 µm
microvia pad
ø 300 µm
on layer 4
0.40 mm pitch
BGA pad ø 350 µm
track width 90 / 100 µm
solder mask clearance 50 µm
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blue = outer layer
green = solder mask
red = layer 2
black = layer 3
violet = layer 4
Version 1.2 / September 2018