Nano Porous Gold as a Capping Layer for Thin Film Encapsulation

Author

Jae-Wung Lee ; Wei-Shan Wang ; Sharma, Jaibir ; Yu-Ching Lin ; Singh, Navab

Author_Institution

Inst. of Microelectron., A*STAR (Agency for Sci., Technol. & Res.), Singapore, Singapore

Volume

22

Issue

5

fYear

2013

fDate

Oct. 2013

Firstpage

998

Lastpage

1000

Abstract

This paper reports Nano Porous Gold (NPG) thin film as a cap layer for encapsulating MicroElectroMechanical System (MEMS) devices. The uniformly distributed zig-zag nanopores in the NPG cap structure reduce the release time as well as protect the MEMS devices from the mass loading during the sealing process, thus solving the two main problems in thin film encapsulation (TFE) process. Using 0.5-μm thick NPG cap in combination with silicon dioxide as sacrificial layer, we could release 400 μm×400 μm×3 μm cavities in vapor-HF within 10 min, which is 16 times faster than the TFE fabricated using a conventional sidewall located release channel with nonporous films. No mass loading and damage were noticed while sealing the cap using silicon dioxide.

Keywords

encapsulation; gold; micromechanical devices; nanoporous materials; seals (stoppers); silicon compounds; thin films; Au; MEMS devices; NPG cap structure; SiO₂; capping layer; mass loading; microelectromechanical system devices; nanoporous gold thin film; release time; sacrificial layer; sealing process; sidewall located release channel; silicon dioxide; size 0.5 mum; thin film encapsulation; time 10 min; uniformly distributed zig-zag nanopores; MEMS; Thin film encapsulation; nano porous gold; packaging; release time;

fLanguage

English

Journal_Title

Microelectromechanical Systems, Journal of

Publisher

ieee

ISSN

1057-7157

Type

jour

DOI

10.1109/JMEMS.2013.2265393

Filename

6553061