AuSn PASTE
Solution
Chips can be bonded to rough
or warped substrates
Challenge
Bond strength is not stable due to substrate roughness
- When a chip with a AuSn deposition film is bonded, the surface of the substrate is rough and does not attach properly.
- When a chip with a AuSn deposition film is bonded, the warp of the substrate is large and does not attach properly.
Solution Overview
AuSn paste is a solder paste that is a mixture of AuSn powder and flux. In addition to flexibility in the supplying shape, since it contains a flux that accelerates the wetting and spreading of the solder, it can fill into the uneven parts of the substrate and get wet, and good bonding can be obtained.
Effect
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Before
When a chip with a AuSn deposition film is used, since the surface of the substrate is rough / the substrate is greatly warped, the part where the AuSn layer is not in contact remains unwetted even after reflow.
-
After
Even if the substrate has surface roughness and / or warpage, the fill into the parts where the distance between the substrate and the chip are uneven, thus good bonding can be obtained.
MOVIE
This video shows a comparison between the bonding of chips with AuSn deposition film, and AuSn paste. AuSn paste ensures good bonding conditions and bonding strength.
ADVANTAGE
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ADVANTAGE01
Since it is a paste, it can flexibly handle unevenness on the substrate.
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ADVANTAGE02
The AuSn paste can also flexibly handle the warpage of substrates that are difficult to bond with AuSn deposition films.
OTHER SOLUTIONS
Other solutions for AuSn paste
-
AuSn PASTE
Hope to flexibly change the thickness and shape of AuSn
-
AuSn PASTE
The chip is misaligned when bonding
-
AuSn PASTE
Hope to reduce the cost of the cleaning process
-
AuSn PASTE
There are problems when using paste in mass production
Other related solutions
This solution utilizes
Mitsubishi Materials' AuSn paste.