Abstract

Generally, microelectro mechanical systems (MOEMS) devices require encapsulation for protecting their fragile and tiny inner components in a hermetically sealed cavity. Cavity hermeticity can be critical to the device performance and plays a vital role with respect to reliability and long-term drift characteristics of the MOEMS products. The paper presents a theoretical approach for estimation of lifetime of MOEMS devices in terms of cavity’s hermeticity to gases and water. The results are summarized as working maps for MOEMS packaging engineers, in terms of device cavity (internal package volume), equivalent leak rates, and equivalent size of interconnected defects in the bonding zone.

1.
Jung
,
E.
, 2003, “
Packaging Options for MEMS Devices
,”
MRS Bull.
0883-7694,
28
(
1
), pp.
51
54
.
2.
Forehand
,
D.
, 2005, “
Wafer-Level Microencapsulation
,”
Distinguished Lecture Series in Nano & Micro-Systems
, University of Texas at Arlington, Arlington, TX.
3.
Tilmans
,
H. A. C.
,
Van de Peer
,
M. D. J.
, and
Beyne
,
E.
, 2000, “
The Indent Reflow Sealing (IRS) Technique—A Method for the Fabrication of Sealed Cavities for MEMS Devices
,”
J. Microelectromech. Syst.
1057-7157,
9
, pp.
206
217
.
4.
Tao
,
Y.
, and
Malshe
,
A. P.
, 2005, “
Theoretical Investigation on Hermeticity Testing of MEMS Packages Based on MIL-STD-883
,”
Microelectron. Reliab.
0026-2714,
45
, pp.
559
566
.
5.
Mack
,
S.
,
Baumann
,
H.
, and
Gösele
,
U.
, 1996, “
Gas Tightness of Cavities Sealed by Silicon Wafer Bonding
,”
Proceedings of the 10th IEEE International Workshop on MEMS
, Nagoya, Japan, January 26–30, pp.
488
493
.
6.
Nese
,
M.
,
Bernstein
,
R. W.
,
Johansen
,
I.-R.
, and
Spooren
,
R.
, 1996, “
New Method for Testing Hermeticity of Silicon Sensor Structure
,”
Sens. Actuators, A
0924-4247,
53
, pp.
349
352
.
7.
Nylander
,
C.
, 2006, “
Fast, Reliable Leak Detection
,” http://www.process-cooling.comhttp://www.process-cooling.com
8.
Leak Detection of Automotive Components
,” http://www.varianinc.comhttp://www.varianinc.com
9.
Personal correspondence with Professor
Shai
,
I.
,
Ben-Gurion
, University of the Negev, Israel.
10.
Thornberg
,
S. M.
, 1988, “
Stepped Linear Piston Displacemnet Fundamental Leak Calibration
,”
J. Vac. Sci. Technol. A
0734-2101,
6
(
4
), pp.
2522
2527
.
11.
Hyland
,
W. H.
,
Enrilch
,
C. D.
,
Tilford
,
C. R.
, and
Thornberg
,
S. M.
, 1986, “
Transfer Leak Studies and Comparisons of Primary Leak Standrads at the National Bureau of Standards and Sandia National Laboratories
,”
J. Vac. Sci. Technol. A
0734-2101,
4
(
3
), pp.
334
337
.
12.
Roth
,
A.
, 1990,
Vacuum Technology
, 3rd ed.,
North–Holland
,
Amsterdam, The Netherlands
.
13.
Dushman
,
S.
, and
Lafferty
,
J. M.
, 1962,
Scientific Foundations of Vacuum Technique
, 2nd ed.,
Wiley
,
New York
.
14.
Greenhouse
,
H.
, 2000,
Hermeticity of Electronic Packages
,
Noyes and William Andrew
,
New York
.
15.
Department of Defense, 1997, Paper No. MIL-STD-883E.
16.
Sonntag
,
R. E.
,
Borgnakke
,
C.
, and
Van Wylen
,
G. J.
, 2003,
Fundamentals of Thermodynamics
, 6th ed.,
Wiley
,
New York
.
17.
Howl
,
D. A.
, and
Mann
,
C. A.
, 1965, “
The back-pressurization technique of leak testing
,”
Vacuum
0042-207X,
15
, pp.
347
352
.
18.
Feldman
,
K.
,
Bar-Kohany
,
T.
, and
Stern
,
A.
, 2005, “
Detection of Fine Leaks in MOEMS Hermetic Sealed Cavities
,”
Proceedings Welding and Joining—IIW International Conference
,
Tel Aviv, Israel
, January 25–28.
19.
Stern
,
A.
,
Kemelman
,
M.
,
Bar-Kohany
,
T.
, and
Feldman
,
K.
, 2005, “
Hermetic Encapsulation of MOEMS by Fluxless Soldering
,”
Proceedings Welding and Joining—IIW International Conference
,
Tel Aviv, Israel
, January 29–30.
20.
Bar-Kohany
,
T.
, and
Stern
,
A.
, 2005, “
Leak Testing of MOEMS—Theory and Practice
,”
Proceedings 30th Israeli Conference on Mechanical Engineering
,
Tel Aviv, Israel
, January 29–30.
21.
Department of Defense, 2002, Paper No. MIL-PRF-385354F and 5F.
23.
Jourdain
,
P.
,
De Moor
,
P.
,
Pamidighantam
,
S.
, and
Tilmans
,
H. A. C.
, 2002, “
Investigation of the Hermeticity of BCB-Sealed Cavities for Housing (RF-) MEMS Devices
,”
Proceedings of the 17th IEEE International Conference on MEMS
, Las Vegas, NV, January 20–24, pp.
677
680
.
24.
Glien
,
K.
,
Heppel
,
K.
,
Graf
,
J.
,
Müller-Fiedler
,
R.
, and
Höfer
,
H.
, 2004, “
Gas Permeability and Hermeticity of Glass Frit Bonded Micro Packages
,”
Proceedings Workshop on Wafer Bonding for MEMS Technologies
,
Halle, Germany
, October 11–12.
You do not currently have access to this content.