Special Topic
2
Technical trends in filters for
1
These days we can see more and more applications being installed in communication
devices, W-LAN in notebook PCs, Bluetooth and digital terrestrial broadcasting
applications in cellular phones.
In the future, wireless communication and broadcasting technologies will continue
to further develop, and the wireless market which supports them , including wireless
components, will further expand as well.
In this ubiquitously connected society, ICs used in communication systems, and wireless
devices are required to be high-performance, smaller, and inexpensive.
In this article, we will explain filter processes, Taiyo Yuden's filter lineup, and notification
for using filters in desigs in such wireless devices.
The materials of multilayer filters
Multilayer ceramics filters, which are used for
frequency bands ranging from several hundreds
MHz to several GHz, are composed of low-resist-
ance conductor materials, such as Ag and Cu, and
dielectric materials. The conductor materials are
mainly composed from Ag-based materials.
This dielectric material contains an Ag con-
ductor, so we use low temperature co-fired
ceramic(LTCC) materials, which can be baked
The manufacturing process of
multilayer filters
Figure 1. Process-Flow Diagram
Mixing/Casting
The manufacturing process of ceramic compo-
nents for wireless application, such as multilayer
Cutting
Laminating
filters, is described in
. Except for the
Figure 1
Firing
Cutting Sheet
inspection process, multilayer filters can be pro-
duced by similar process flow to other multilayer
components such as multilayer inductors.
Forming terminal
Making Via Hole
electrodes
Int. Conductor pattern
screening/printing
Plating
Inspection
Shipment
Filter characteristics are significantly affected by
the accuracy of manufacturing processes. These
characteristics are the material dielectric constant,
thickness of dielectric layer, printing process,
Stacking/bonding
at 900 , rather than using capacitor's dielectric
℃
materials, which can be baked at 1,300
.
℃
2008
Taiyo Yuden Navigator
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