Enhanced Polymer Passivation Layer for Wafer Level Chip Scale ...
Enhanced Polymer Passivation Layer for Wafer Level Chip Scale ...
Enhanced Polymer Passivation Layer for Wafer Level Chip Scale ...
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cutting speed was set at a low value (80mil/sec) to avoid peeling the SolderBrace material off of<br />
the silicon, and to reduce the loading on the blade. All of the singulated dies were cleaned, dried,<br />
and then stored in a dry box after dicing, ready <strong>for</strong> surface mount assembly. The cross section of<br />
a standard WLCSP solder ball and a solder ball on a SolderBrace coated WLCSP are shown in<br />
Figure 4.1.<br />
Table 4.1 Specifications <strong>for</strong> wafer dicing<br />
Spindle Speed 2200 rpm<br />
Cutting Speed 80 mil/sec<br />
Film Height 2 mil<br />
<strong>Wafer</strong> thickness 20 mil<br />
(a) (b)<br />
Figure 4.1 Cross-section of Standard (a) and SolderBrace coated (b) Solder Ball<br />
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