Thin-Film RF/Microwave Capacitor Technology
Automotive Grade Accu-P® Series
Thin-Film Technology
THE IDEAL CAPACITOR
THIN-FILM TECHNOLOGY
The non-ideal characteristics of a real capacitor can be ignored at low
frequencies. Physical size imparts inductance to the capacitor and
dielectric and metal electrodes result in resistive losses, but these often
are of negligible effect on the circuit. At the very high frequencies of radio
communication (>100MHz) and satellite systems (>1GHz), these effects
become important. Recognizing that a real capacitor will exhibit inductive
and resistive impedances in addition to capacitance, the ideal capacitor for
these high frequencies is an ultra low loss component which can be fully
characterized in all parameters with total repeatability from unit to unit.
Thin-film technology is commonly used in producing semiconductor devices.
In the last two decades, this technology has developed tremendously, both
in performance and in process control. Today’s techniques enable line
definitions of below 1μm, and the controlling of thickness of layers at 100Å
(10-2μm). Applying this technology to the manufacture of capacitors has
enabled the development of components where both electrical and physical
properties can be tightly controlled.
The thin-film production facilities at KYOCERA AVX consist of:
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Class 1000 clean rooms, with working areas under laminar-flow hoods
of class 100, (below 100 particles per cubic foot larger than 0.5μm).
High vacuum metal deposition systems for high-purity
electrode construction.
Photolithography equipment for line definition down to 2.0μm
accuracy.
Plasma-enhanced CVD for various dielectric depositions
(CVD=Chemical Vapor Deposition).
High accuracy, microprocessor-controlled dicing saws for
chip separation.
High speed, high accuracy sorting to ensure strict tolerance adherence.
Until recently, most high frequency/microwave capacitors were based on
fired-ceramic (porcelain) technology. Layers of ceramic dielectric material
and metal alloy electrode paste are interleaved and then sintered in a
high temperature oven. This technology exhibits component variability in
dielectric quality (losses, dielectric constant and insulation resistance),
variability in electrode conductivity and variability in physical size (affecting
inductance). An alternate thin-film technology has been developed which
virtually eliminates these variances. It is this technology which has been
fully incorporated into Accu-P® and Accu-P® to provide high frequency
capacitors exhibiting truly ideal characteristics.
The main features of Accu-P® may be summarized as follows:
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High purity of electrodes for very low and repeatable ESR.
Highly pure, low-K dielectric for high breakdown field, high insulation
resistance and low losses to frequencies above 40GHz.
Very tight dimensional control for uniform inductance, unit to unit.
Very tight capacitance tolerances for high frequency signal
applications.
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This accuracy sets apart these Thin-Film capacitors from ceramic capacitors
so that the term Accu has been employed as the designation for this series
of devices, an abbreviation for “accurate.”
Orientation Marking
Alumina (Al2O3)
Electrode
Seal
(SiNO)
Dielectric (SiO2 / SiNO)
Electrode
Alumina (Al2O3)
Terminations
ACCU-P® CAPACITOR STRUCTURE
The Important Information/Disclaimer is incorporated in the catalog where these specifications came from or available
online at www.kyocera-avx.com/disclaimer/ by reference and should be reviewed in full before placing any order.
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TDS-RFM-0041 | Rev 1
rf microwave products
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