TY - JOUR A1 - Schober, Jakob A1 - Eulenkamp, Constanze A1 - Nicolaus, Karl A1 - Feiertag, Gregor T1 - Reliability Study of Miniaturized Surface Acoustic Wave RF-Filters With Copper Pillar Bump Interconnections T2 - IEEE Access, Volume 9,2021 N2 - Microacoustic radio frequency filters are essential electronic components for all devices using wireless communication. For miniaturization and cost reduction it is necessary to further reduce the area for the electrical contacts on the chip. CPB (copper pillar bump) interconnections on radio frequency filters can release valuable chip design area of up to 26 % compared to standard SB (solder bump) interconnections on a Qualcomm TFAP (Thin Film Acoustic Package). We developed a process to deposit CPB interconnections on microacoustic radio frequency filters. A 1.20 mm × 1.60 mm SAW (surface acoustic wave) LTE (Long Term Evolution) band 26 duplexer with a height of 0.20 mm including the CPB interconnections was investigated. Unbiased highly accelerated stress test, damp heat steady state, dry heat, and temperature cycling reliability tests have shown that the new interconnection technology fulfills the reliability requirements of the smart device industry. Two failure modes caused by extended temperature cycling were identified via scanning acoustic microscopy and scanning electron microscopy analyses on cross sections. KW - Dünne Schicht KW - Mikroelektronik KW - Mobilfunk Y1 - 2022 UR - https://opus4.kobv.de/opus4-hm/frontdoor/index/index/docId/383 UR - https://nbn-resolving.org/urn:nbn:de:bvb:m347-opus-3831 SP - 14581 EP - 14589 PB - IEEE ER -