Technical Library | 2022-10-31 09:05:54.0
Warranty: 3 Months Precision: High Precision Certification: CE，ROHS Wight: 1kg Automatic Grade: Automatic Trademark: Ultra High-speed Chip Mounter High Light: 00345186, 00345186 smt pick and place parts, 00345186 SMT Spare Parts
Technical Library | 2022-10-31 09:18:09.0
Model: STRIPPING DEVICE PLATE Type: High-speed Chip Mounter Brand: SIEMENS SIPLACE ASM QUALITY: 100% Tested Usage: SIPLACE SMT Placement Machine HIGH LIGHT: Surface Mount Components, Smt Machine Part High Light: 00341941S01 SMT Spare Parts, 12*16mm SMT Spare Parts, 00341941S01
Technical Library | 2017-07-06 15:50:17.0
Head-in-pillow (HiP) is a BGA defect which happens when solder balls and paste can't contact well during reflow soldering. Package warpage was one of the major reasons for HiP formation. In this paper, package warpage was measured and simulated. It was found that the package warpage was sensitive to the thickness of inside chips. A FEM method considering viscoelastic property of mold compound was introduced to simulate package warpage. The CTE mismatch was found contributes to more than 90% of the package warpage value when reflowing at the peak temperature. A method was introduced to measure the warpage threshold, which is the smallest warpage value that may lead to HiP. The results in different atmospheres showed that the warpage threshold was 50μm larger in N2 than that in air, suggesting that under N2 atmosphere the process window for HiP defects was larger than that under air, which agreed with the experiments.
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