C7-Graphite-1738M Graphite Tool for precision positioning of 0.4mm diameter Micro-coil springs onto BGA1738 organic substrates is an alternative to conventional solder balls.
Micro-coil springs provide compliant interconnects between IC packages and the PCB. The footprint of 1738 packages is 42.5 x 42.5mm with a pad pitch of 1.0mm. After attaching Micro-coil springs, the reworked package provides more compliancy than BGA solder balls to absorb stress caused by CTE mismatch, and to increase solder joint reliability under harsh operating conditions. Securely locks organic or ceramic LGA substrates in place while Micro-coil springs are attached to the substrate. The procedure is simple: an operator places the LGA inside of the Graphite Tool. Next, a layer of solder paste is printed on the LGA pads using a 125um thick stainless-steel stencil. Afterwards, Micro-coil springs are dropped in place using TopLine's patented Flip-Pack cassette. After depositing the springs into the graphite, the operator removes the Flip-Pack. The next step is to place the graphite into a vapor-phase reflow oven to form solder fillets that permanently secures the Micro-coil spring to the IC substrate. After cool-down, the CGA is gently removed using an engineered extraction tool. Patent pending.
TopLine
http://www.topline.tv/CCGA_Tool.html
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