EPOXY STAMPING & DISPENSING TOOLS
In general, dispensing can be defined as transfer of fluid from a
container (typically in syringe) to a substrate in a form of pattern or
calculated volumes to host a die or component. In electronics industry, there
are various methods that have evolved to keep up with the rapid development
of manufacturing need for adhesives and conductive epoxies in a wide array of
packaging assemblies.
Over the years, dispensing applications have expanded to other areas
needed for new types of packaging encapsulation techniques. A wide variety of
fluid materials with different viscosity are being used, from solder paste,
conductive adhesives and damming compound to fluxes, thermal paste and
underfills.
DISPENSING PROCESS AND TECHNOLOGY
Stamping:
Sometimes known as daubing or pin transfer, this method involves dipping a
compliant tool into a reservoir of liquid material then transferring the
adhering liquid onto a substrate. This method is frequently used to attain
very small dots. However, the process is considered slow as compared to other
methods especially if the application requires multiple dots dispensing. To
increase throughput, gang (multiple) stamping tool can be employed to stamp
an array of dots simultaneously. Grid type stamping tool is also available to
print a large area.
Stencil Printing:
Stencil printing is the fastest and most efficient way of applying
adhesive to a large area in mass production runs. In this method, a patterned
stencil is placed over the substrate and a squeegee force the material
through the stencil apertures onto the substrate. This may become complicated
when the stencil apertures become so small that the material can no longer
print effectively.
Jet-dispensing:
Non-contact jet-dispensing is one of the newer methods in dispensing
technologies. Shots of fluid are fired onto the substrate in a non-contact
process. Since dispensing dots are typically restricted to one specific size
during a run, larger volumes are achieved by accumulating multiple dots. By
moving the jet head during deposition, required patterns can be formed.
Nozzle or Needle Dispensing:
In this method, time and air pressure is commonly used to push the fluid
through a needle or nozzle to form single dot or multiple dot patterns over
the substrate. Over the years, various dispensing platforms with programmable
pumps and valves, such as auger and piston have been developed to achieve
unique patterns or volumes using single needle or special tapered nozzle.
These platforms could either be stand-alone dispensing equipment or
integrated on those new pick and place machines.
ASM 809, Alphasem Easyline, Amica, Assembly Tech, ESEC 2005
/ 2006 / Micron 2 / Micron 5003, ESC, Datacon, Delvotec, Air Vac, Dr Tresky
Flip Station,
Foton, Hacker, Hughes, ISMECA SDB1000 / ADB2000, K&S 6300 / 6900, KME, Laurier,
MRSI 505, Muehlbauer, Palomar HG1 / HG2, Quad APS1, SEC (Semiconductor Equipment
Corp) Model 850, Model 860, Model 410, Model 830, KTM83A, KTM 83B, Shinkawa, Toshoko,
Universal, West Bond, Viking Semicon and other die bonders.
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