Reliable transportation mechanism for micro solder balls
A solder ball bonding (SBB) tool includes a rotatable feed plate for transporting solder balls from a translatable solder ball reservoir to a nozzle unit, which is a position at which a laser light source can irradiate and thus melt the solder balls. The SBB tool includes a gap between the reservoir and the feed plate positioned over the reservoir, and a feed mechanism coupled with the reservoir, where the feed mechanism is driven by a pressurized gas to translate the reservoir upward across at least a portion of the gap in preparation for movement of a solder ball to the feed plate and downward in preparation for rotation of the feed plate after a solder ball is moved to the feed plate. The gap may have a maximum size that exceeds a nominal size of the solder balls contained in the reservoir.
1. A solder ball bonding tool, comprising:
a translatable feed mechanism comprising:
an upward pressurized gas delivery mechanism for upwardly translating said feed mechanism,
a downward pressurized gas delivery mechanism for downwardly translating said feed mechanism,
a solder ball pressurized gas delivery mechanism,
a central chamber, and
a translatable solder ball reservoir configured for housing solder balls, wherein said solder ball pressurized gas delivery mechanism supplies pressurized gas through said central chamber of said feed mechanism into said reservoir;
a rotatable feed plate having a plurality of holes for receiving a solder ball from said reservoir via said pressurized gas through said central chamber and for feeding said solder ball into a nozzle unit and for guiding laser light from a laser light source onto said solder ball; and
said nozzle unit configured for directing said solder ball into a nozzle and ejecting said solder ball from said nozzle onto a work piece.
2. The solder ball bonding tool of claim 1 , wherein said feed mechanism is driven upward via pressurized gas supplied through said upward delivery mechanism to translate said reservoir upward and said feed mechanism is driven downward via pressurized gas supplied through said downward delivery mechanism to translate said reservoir downward.
3. The solder ball bonding tool of claim 1 , wherein said reservoir is positioned below said feed plate with a gap in between, and wherein said reservoir is translatable in a vertical direction across most of said gap into near contact with said feed plate.
4. The solder ball bonding tool of claim 3 , wherein a maximum size of said gap exceeds a nominal size of said solder balls.
5. The solder ball bonding tool of claim 1 , further comprising:
a maximum gap between said reservoir and said feed plate positioned over said reservoir; and
wherein said feed mechanism is driven upward via pressurized gas supplied through said upward delivery mechanism to translate said reservoir upward across at least a portion of said maximum gap in preparation for movement of a solder ball into one of said holes of said feed plate, and wherein said feed mechanism is driven downward via pressurized gas supplied through said downward delivery mechanism to translate said reservoir downward in preparation for rotation of said feed plate after said solder ball is moved into said one hole.
6. The solder ball bonding tool of claim 1 , wherein said feed plate is configured with a plurality of first holes for receiving said solder ball from said reservoir and for feeding said solder ball into a nozzle unit and a plurality of second holes separate from said plurality of first holes and for providing an aperture for said laser light to irradiate said solder ball.
7. The solder ball bonding tool of claim 6 , wherein said first and second holes are configured alternately in said feed plate.