Transcript Ragan Technologies, Inc. Presents

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Ragan Technologies Inc.
Ragan Technologies, Inc.
Presents - Zero Shrink
Technology - ZST™
Process for Embedding Fired
Multi-Layer Capacitors in
LTCC Packages
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Ragan Technologies Inc.
Ragan Technologies ZST™
Overview
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Who is RTI?
What is ZST™?
What is passive integration?
What are the benefits of passive integration?
What are the benefits of ZST™ for capacitor
integration?
Process used to embed fired capacitors in ZST™
Summary
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Ragan Technologies Inc.
Who is RTI?
Ragan Technologies, Inc. is a privately
held technology transfer company
based in San Diego, CA.
 RTI offers turn-key technology
development services specializing in
tape forming and electronic ceramics.
 The founders of RTI have over 190
years of cumulative experience in the
technical ceramics industry.
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What is ZST™?
ZST™ is a unique low temperature cofire tape CAPABILITY for MCM
production.
 ZST™ is not a new material, but a
process.
 With this new patented process, sheets
can be produced that do not shrink
when fired.
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What is ZST™?
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By controlling the particle size
distribution of the frit, the resulting
shrinkage can controlled.
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The process has been tested with
thousands of combinations of refractory
oxides and frits.
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What is ZST™?
By adjusting the raw materials, tapes
can be made with:
High K or low K
High CTE or low CTE
Thermal conductor or insulator
Electrical conductor or insulator
Porous or hermetic
AND all sheets can be co-fired because
they will not shrink when fired!
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What is ZST™?
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With this new process, RTI has created
new engineering degrees of freedom.
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Because the ceramic does not shrink
when fired, it is possible to embed solid
articles in the green tape such as...
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What is ZST™?
Solid metal wires or ribbons for high
power leads or lead frames
 Fired BeO thermal spreaders
 Fired alumina die to form a non-reactive
resistor printing pad
 Resistive or Inductive components
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What is ZST™?
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Eliminate costly yield problems
associated with shrinkage variation.
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Shrinkage tolerances of 0.03% typical.
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Precise feature location for closer pitch
vias and lines.
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What is ZST™?
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Create high strength composites by
building up the circuit on fired alumina.
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ZST™ forms strong oxide bond.
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Resultant composite flexural strength
approaches that of alumina. (>250MPa)
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What is passive integration?
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Passive integration is the process of
incorporating passive components
(specifically capacitors, resistors, and
inductors) into the MCM substrate or
integrated circuit package.
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Benefits of passive integration
Increased circuit density
 Decreased circuit size
 Reduced weight
 Shorter leads
 Fewer interconnects
 Improved electrical performance
 Lower costs in volume production
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Capacitor integration with
ZST™
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Current technology is to print the conductor
plates on subsequent layers of the LTCC tape
and form the capacitors as the circuit is
stacked.
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This process is limited by the K of the LTCC,
the thickness of the tape, and the resolution
and precision of the printer.
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Capacitor integration with
ZST™
Embedding pre-tested multi-layer ceramic
capacitors in ZST™…
“Known good die” concept
 Broad range of dielectric types
 Fewer interconnects = improved signal
integrity
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Capacitor integration with
ZST™
Facilitates automation - single pick and place
operation replaces multiple printing
operations and solder re-flow yield problems.
 Facilitates miniaturization - increased
volumetric efficiency = smaller circuit
 Improved reliability - eliminate yield losses
due to shorts and opens associated with
screen printed capacitors in LTCC.
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Process for embedding fired
capacitors in ZST™
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Ragan Technologies Inc.
Process sequence:
Print conductors
 Punch sheets
 Stack sheets
 Insert capacitors
 Laminate
 External metalization
 Fire
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Design substrate
 For demonstration purposes a simple two inch
square substrate was designed with five buried
capacitors.
 Two dielectrics tested:
 1206 X7R 0.1µF
 1206 NPO 33pF
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Print conductors
The conductor traces were printed on the base
layer with Heraeus C4740L Ag conductor paste and
dried.
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Punch cavities
Subsequent two layers were punched to form the
cavity for the 1206 case size.
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Insert capacitors
The capacitors were inserted into the cavity, with
their terminations aligned over the printed pads.
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Lamination
 The cover sheet was then placed and the stack
was iso-statically pressed in a die.
 2500psi - 10 min. - 50ºC
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Co-Fire
The substrate was then metalized with the Ag
conductor paste and fired.
– 875ºC/30 min.
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Capacitance measurement
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The capacitance and DF of the embedded chips
was verified after firing.
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Thermal Cycling
Preliminary thermal cycling tests were
positive…
 0ºC to 100ºC to 0ºC - 20 cycles
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0ºC soak 1 minute (ice water)
Transfer into boiling water 10 seconds
100ºC soak 1 minute
Transfer into ice water 10 seconds
Repeat
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Summary
ZST™ offers unique solutions to design
problems:
Absolute shrinkage control - eliminate variation
 Control electrical properties - K etc.
Control mechanical properties - CTE etc.
Embed solid objects - metal & ceramic
These properties can be co-fired together,
because the shrinkage is CONTROLLED
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