High-G drop impact response and failure analysis of a chip packaged printed circuit board

A simply constructed but efficacious shock tester for high-g level shock simulation

“…Current high-g level testing methods commonly used on lightweight components include the rail gun, air gun, free fall drop test, live fire test, Hopkinson Bar, pendulum striker, hammer below, piezo-actuators, and half-sine shock machines. [5][6][7][8][9][10][11][12][13] With the uses of a Mass Shock Amplifier, such as the Model MSA-89 × 89 developed by L.A.B. Equipment Inc., 14 such shock machines can generate accelerations as high as 100 000 g.…”

Solder joint and trace line failure simulation and experimental validation of fan-out type wafer level packaging subjected to drop impact

“…The results revealed that the stress-buffer-enhanced package survived over 100 drops. Moreover, the failure occurred at the interconnection of the package which is markedly different from the failure mode at solder joint observed in the drop test experiments of conventional wafer level package (WLP) [6,7].…”

“…The proposed stress-buffer-enhanced package reveals a much better reliability of drop test compared with conventional wafer level package (WLP). In addition, the position of first failure varied from that of previous studies [6] which located near the center of PCB (U3, U8, U13). The WLP drop test analysis disclosed the solder joint cracks along intermetallic compound (IMC) layer as the main cause of failure; in this study, however, broken metal lines in packages instead of solder joint fractures were perceived to be the reason of failure as shown in Fig.…”

Interfacial reaction between Sn1Ag0.5Cu(Co) solder and Cu substrate with Au/Ni surface finish during reflow reaction

“…rate fracture resistance, and reducing Ag content is highly effective in increasing bulk compliance and plastic energy dissipation ability, resulting in significant performance enhancement during drop testing. Suh et al and some other researchers [1][2][3] have also reported that Sn 1 wt.% Ag 0.5 wt.% Cu (SAC105) alloy and other low-Ag alloys exhibit significantly higher fracture resistance under high-strain rate conditions than SAC405 and SAC305 alloys. Nevertheless, compared with high-Ag alloys, such as SAC405 and SAC305, the SAC105 had lower elastic modulus and tensile strength due to reduced Ag content [1].…”