Bevel cutting
Bevel cutting creates a V groove in the substrate. The major issues
to consider are bottom side chipping and smoothness of the cut
surface. The simplest bevel cut involves mounting the substrate
on dicing tape and cutting about 0.001” into the tape. This
allows the singulated parts to be cleaned and removed from the
tape easily. The difficulty is that the tape does not support the
bottom side of the substrate very well, resulting in bottom side
chips of up to several mils.
Wax mounting the substrate on glass gives better bottom side support
and consequently less chipping. The trade off is that the final
dice are more difficult to remove and clean.
A third alternative is to tape mount the substrate, but to make
the groove 50% to 75%
of the depth of the substrate. A second isolation cut with a narrow
blade to minimize chipping can then be performed.
Let one of the engineers at Kadco evaluate
your cutting requirements. We will make recommendations and provide
samples if necessary to make sure your chips meet specifications.
Back to Top of Page
|
Burr Free Dicing
Whenever a diamond tool cuts through a soft metal such as gold,
some kind of burr will form on the cut edge. Frequently we can
select combinations of blades and speeds which will minimize the
burr. For example, a 1 mil burr on a capacitor with a coating of
200 microinches of gold is usually not a problem.
However, in some applications even this small burr is unacceptable.
In that case Kadco can provide chemical etching and vibratory finishing
operations that will remove the burr and etch back the metallization
from the cut edge. Contact our engineers at Kadco
and we will discuss the best solution to your problem.
Back to Top of Page
|
Chip Free Dicing
A diamond saw removes brittle material by chipping it out. Chip
out will occur at some level. The important issue is to keep the
chipping within the final product specifications. Chipping can
be controlled with careful attention to the dicing process parameters:
feed, speed, coolant flow, blade exposure and composition, mechanism
of mounting the substrate, and selection of substrate materials.
Kadco’s engineers have had experience
with many very tight chipping specifications. Let us apply our
experience to your requirements.
Back to Top of Page
|
Cleaning & Packaging
 Cleaning
and packaging dice can add considerable expense to the final product.
Since dicing is an inherently dirty operation, debris will form during
the operation. The most common and economical approach is usually to
provide a final cleaning after dicing. The dice can then be packaged
in bulk or in chip carriers for transport.
An alternative is to coat the substrate with a protective material
before dicing. This avoids having the debris come in contact with
the substrate surface during the cutting operation. The coating
can then be removed before final packaging or simply remain in
place until the next manufacturing operation. Kadco has considerable
experience avoiding or cleaning up contamination. Let us discuss
your concerns before they become problems.
Back to Top of Page
|
Die singulation
Die singulation requires some kind of mounting medium to hold
the substrate as it is being cut. This is usually either tape on
a film frame or wax on glass, although mounting directly on a vacuum
chuck will work in some cases. The cut can then be a scribe for
subsequent breaking or a thru cut. Scribing is convenient, but
usually results in more chips and rough edges. Thru cuts on tape
give tighter tolerances on the final chip size, but may result
in some bottom side chipping. Wax mounting on glass normally gives
the best edge quality, but requires demounting and cleaning.
Whatever your requirements, give us a call at Kadco to lay out
a program to meet your specifications.
Back to Top of Page
|
Fiber optic polishing
Fiber optics require very smooth cuts at precise angles to minimize
subsequent polishing time. Kadco has experience
designing fixturing which will simplify your process. Let our engineers
make a proposal which will eliminate multiple steps of tedious hand
mounting and demounting.
Back to Top of Page
|
Isolation cutting
 Isolation
cutting creates electrical separation between circuit elements
on a die. A typical application is to create electrically isolated
pads on the gold coated surface of a capacitor. Important considerations
are the depth of the isolation cut, the width of the cut, and cleanliness.
Residual debris in the groove or on the surface can compromise
the isolation.
Kadco has engineering expertise in mounting
and cleaning to meet your requirements. Give us a call to discuss
your problem and provide samples where necessary.
Back to Top of Page
|
Plated Thru Holes
 Plated
thru holes are sometimes necessary for good grounding of microwave
circuits. To insure good yields the size and positioning of these
holes must be carefully considered at the design stage. Kadco has
experience fabricating plated thru holes under 0.010” diameter
with thin film resistors in close proximity. Call us to discuss your
design plans so we can help you find economical solutions to your
problems.
Back to Top of Page
|
Substrate edge chamfering
Substrate edges may require chamfering for a number of different
reasons. This usually requires careful layout of the patterns on
the substrate to avoid edge cuts. A 45° chamfer, for example,
requires substrate material to be on both sides of the blade to
avoid sideways deflection of the blade and possible breakage.
Let the engineers at Kadco help you lay
out the patterning early in your project to avoid problems later.
Back to Top of Page
|
Substrate grooving & slotting
Substrates might require grooves for electrical isolation or for
fixturing requirements. Some of the potential difficulties that
require prior planning are width and depth tolerances, flatness
of the bottom of the groove, and squareness of the corners.
You can avoid problems by discussing your requirements with the
engineering staff at Kadco early in your
project.
Back to Top of Page
|
Thin Film Resistors
Thin film resistors are usually made from a sputtered layer of tantalum
nitride (TaN), or nichrome (NiCr) with a specific resistance of 10 – 100
O/?. A typical resistor tolerance is ± 10% with tighter tolerances
available if necessary. Laser trimming can result in tolerances of
less than ±1%. If you are designing thin film resistors into
you circuit, the engineers at Kadco would
like to discuss your requirements and suggest aspects of your layout
that will reduce manufacturing difficulties and give a more reliable
product.
Back to Top of Page
|
Wafer dicing
Wafer dicing typically means silicon wafer dicing, but may refer
to dicing of any hard material. The wafers can be tape mounted
for ease of handling or wax mounted on glass for more precise cuts.
Kadco can handle all of your dicing needs.
Let our engineers help your formulate the best solution to your
problem.
Back to Top of Page
|
Wafer scribing
Wafers can be scribed for subsequent breaking along the scribe
lines. Typically these wafers are mounted on tape on a film frame
which matches fixturing in subsequent pick and place operations.
Kadco has applications staff available
to discuss your requirements and expedite processing of your order.
Back to Top of Page
|
Wrap Around Metallization
 Wrap
around metallization serves the same function as plated thru holes
in providing good grounding in microwave circuits. There are a
number of different ways to implement wrap around metallization.
Make use of the engineering expertise at Kadco
to find an economical solution to your design requirements.
Back to Top of Page
|
