This is from a section of an ALtera EP2SGX130-5 STRATIX 2 leadfree 1,508 ball BGA. What can be causing this? It is from an unused board (not assembled in a unit, or in the field, but it did pass electrical and function test. There are three of them in the section we did. The lab is calling this pad cratering. The BGA was soldered in a 7 zone Vitronics Soltec oven and when thermocoupled we saw: Peak Temp: 245C, Max Slope: 2.89, Time above liquidus: 62 seconds. We use SAC305 Indium paste. Any help would be appreciated.
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