Reliability Study of Low Cost TSV-Free Interposer (TFI)

The detail process integration of low cost TSV-Free interposer (TFI) was successfully developed and demonstrated. TFI was protected by the underfill and molding compound after Si substrate fully removal. The TFI chips with under bump metallization (UBM) are subjected to thermal cycling (TC) and highly accelerated stress tests (HAST). There is no yield loss after 1000 TC and HAST for TFI chips. Reliability of temperature cycling on board (TCoB) with/without underfill were tested and experimental data are consistent with the results of TC reliability simulation.