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the featured cleaning units are built with Case study: cleaning optimization the crown tips are not expected to make
functionalized abrasive polymer “cleaning In another collaborative project, the sufficient contact with the cleaning
balls” that match the size and layout of the benefits of auto contact cleaning using polymer surface. Two types of cleaning
solder balls on the device under test (DUT). featured cleaning units were investigated units were selected for the evaluation: 1)
During cleaning execution, the “cleaning and characterized. High-volume BGA standard units with a flat “unfeatured”
balls” nest into the socket, centered within devices being tested with floating bed cleaning surface; and 2) featured units
the pin cavities of floating base (Figure sockets were selected. The crown tips with functional cleaning balls that
6). There is precise cleaning ball to pin of the spring pins within the test socket emulated the BGA layout, sizes, and
alignment to facilitate cleaning execution, protruded between 80 to 90µm above the pitches. The cleaning BGA featured
especially when the pins protrude less than floor. Because the spring pins protrude unit for this evaluation is shown in
100µm above the socket floor. less than 100µm above the socket floor, Figure 7a. In the scanning electron

LEADERS IN
MICRO DISPENSING

TECHNOLOGY

SMALL REPEATABLE VOLUMES
ARE A CHALLENGE, BUT NOT
IMPOSSIBLE IF YOU HAVE BEEN
CREATING THEM AS LONG AS WE HAVE.

TO DO IT WELL,
WE PROVIDE THREE THINGS:

Dispensing Expertise in a variety of microelectronic
packaging applications.

Feasibility Testing & Process Verification based
on years of product engineering, material flow testing
and software control.

Product Development for patented valves, Figure 7: Cleaning ball array layout of the cleaning
dispensing cartridges, needles, and accessories. unit is matched exactly to the ball grid array layout of
the actual device under test (DUT): a) Cleaning ball
grid array TCC unit; b) SEM image (X150) of cleaning
balls and abrasive polymer layer of the TCC unit; c)
Three of the cleaning balls’ size, height, and pitch of
the TCC unit.

Our Micro Dispensing product line is proven and trusted by microscope (SEM) image of Figure 7b,
manufacturers in semiconductor, electronics assembly, medical the abrasive particles are visible across
device and electro-mechanical assembly the world over. the surface of the cleaning polymer as
well as within the body of the cleaning
www.dltechnology.com.
balls. The height and pitch of the cleaning
balls were verified and measured using a
216 River Street, Haverhill, MA 01832 • P: 978.374.6451 • F: 978.372.4889 • info@dltechnology.com
3D laser microscope (Figure 7c).

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