Via Filling

Overview of the variations

Wording according IPC 4761
description and options
Image Usual wording
Filled Via

im Portfolio von WE CBT
Type V
via will be filled
completely with
a non-conductive
paste
Filled Via Type V Filled Via / Via Filling

Inner- or outer layer
plugging
Filled &
Covered Via
Type VI-a
the type V via
with dry film
on one side
or liquid
soldermask


Type VI-b
the type V via
with dry film
on both sides
or liquid
soldermask
Filled & Covered Via Type VI-a



Filled & Covered Via Type VI-b
Filled & Covered Via /
Via Filling & Covering



outer layer plugging




Filled &
Capped Via


im Portfolio von WE CBT
Type VII
the type V via
which will be
overplated on both
sides afterwards
Filled & Capped Type VII Filled & Capped Via

Inner- or outer layer
plugging, capped

Via Filling Overplated
im Portfolio von WE CBT = recommended by WE

Initial situation B „opened” vias:

  • Possible solder run-off into vias (solder bridges)
  • In-circuit test
  • Via in pad / SMD
  • High layout density
  • Short circuits (vias under components)

Solutions:

In-circuit test and solder bridges ➜ Use Filled Vias
When dealing with high layout densities, this application is the easiest way to seal the vias airtight.

Avoid short circuits ➜ Use Filled and Covered Vias
In addition to the hermetic seal, the via is covered with solder resist. This electrically insulates the via from the overlying component.

Via in pad / SMD ➜ Use Filled and Capped Vias
Once the vias have been closed, an additional layer of plating over the vias can be used as a solderable surface. This enables a direct connection of a component on top of the via.

Filled Via

Type V

via will be filled
completely with a
non-conductive paste

Filled & Covered Via

Type VI-a

the type V via with
dry film on one side or
liquid soldermask

Filled & Covered Via

Type VI-b

the type V via with
dry film on both sides or
liquid soldermask

Filled & Capped Via

Type VII

the type V via which
will be overplated on both
sides afterwards