Active solid-state devices (e.g. – transistors – solid-state diode – Combined with electrical contact or lead – Ball or nail head type contact – lead – or bond
Patent
1997-07-18
2000-09-05
Monin, Jr., Donald L.
Active solid-state devices (e.g., transistors, solid-state diode
Combined with electrical contact or lead
Ball or nail head type contact, lead, or bond
257786, H01L 2940
Patent
active
061147699
ABSTRACT:
A solder paste brick, for attaching a ball grid array device to a circuit board. The solder paste brick is configured as an irregularly shaped structure so as to reduce distances in which volatized flux gasses must travel in order to escape from within the solder paste brick, thereby reducing voiding in a solder joint formed by the solder paste brick and a solder ball terminal of the ball grid array device as a result of a reflow soldering process. The solder paste brick is further configured so as to allow the solder ball terminal to make contact with a portion of an edge of the solder paste brick, while remaining substantially aligned with a center of a pad of the circuit board, such that a majority of a top surface of the solder paste brick is not in contact with the solder ball terminal. In this way, volatized flux gases formed during a reflow soldering process are caused to escape via the top surface without migrating upwardly into the solder ball terminal during the reflow soldering process.
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MCMS Inc.
Monin, Jr. Donald L.
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