Novel wafer-level CSP for stacked MEMS / IC dies with hermetic sealing

Author

Sugizaki, Yoshiaki ; Nakao, Mitsuhiro ; Higuchi, Kazuhito ; Miyagi, Takeshi ; Obata, Susumu ; Inoue, Michinobu ; Endo, Mitsuyoshi ; Shimooka, Yoshiaki ; Kojima, Akihiro ; Mori, Ikuo ; Shibata, Hideki

Author_Institution

Center for Semicond. R&D, Toshiba Corp., Kawasaki

fYear

2008

fDate

27-30 May 2008

Firstpage

811

Lastpage

816

Abstract

Novel wafer-level chip scale package (WL-CSP) applicable to configurations involving stacking of multiple dies has been developed. Since stacked die makes high topography and it is difficult to apply conventional WL-CSP process, gold bonding wires were used for not only connecting stacked dies with one another but also for connecting from each die to CSP terminals. The WL-CSP is also applicable to microelecrromechanical system (MEMS) that requires hermetic sealing. Thin-film encapsulation for MEMS was formed by conventional back end of line (BEOL) process. Followed by die stacking and gold wire forming, chemical vapor deposition (CVD) was applied to make hermetic sealing. The WL-CSP does not require photolithography process on topography wafer. It promises a cost-effective solution for MEMS/IC dies coupled device.

Keywords

chemical vapour deposition; encapsulation; hermetic seals; micromechanical devices; thin films; wafer level packaging; MEMS-IC dies coupled device; back end of line; chemical vapor deposition; gold bonding wires; hermetic sealing; microelecrromechanical system; stacked MEMS-IC dies; thin-film encapsulation; topography wafer; wafer-level chip scale package; Chip scale packaging; Gold; Joining processes; Micromechanical devices; Stacking; Surfaces; Transistors; Wafer bonding; Wafer scale integration; Wires;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronic Components and Technology Conference, 2008. ECTC 2008. 58th

Conference_Location

Lake Buena Vista, FL

ISSN

0569-5503

Print_ISBN

978-1-4244-2230-2

Electronic_ISBN

0569-5503

Type

conf

DOI

10.1109/ECTC.2008.4550068

Filename

4550068