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Title: Release Resistant Electrical Interconnections For Mems Devices

Abstract

A release resistant electrical interconnection comprising a gold-based electrical conductor compression bonded directly to a highly-doped polysilicon bonding pad in a MEMS, IMEMS, or MOEMS device, without using any intermediate layers of aluminum, titanium, solder, or conductive adhesive disposed in-between the conductor and polysilicon pad. After the initial compression bond has been formed, subsequent heat treatment of the joint above 363 C creates a liquid eutectic phase at the bondline comprising gold plus approximately 3 wt % silicon, which, upon re-solidification, significantly improves the bond strength by reforming and enhancing the initial bond. This type of electrical interconnection is resistant to chemical attack from acids used for releasing MEMS elements (HF, HCL), thereby enabling the use of a "package-first, release-second" sequence for fabricating MEMS devices. Likewise, the bond strength of an Au--Ge compression bond may be increased by forming a transient liquid eutectic phase comprising Au-12 wt % Ge.

Inventors:
 [1];  [1];  [2]
  1. Albuquerque, NM
  2. Corrales, NM
Issue Date:
Research Org.:
Sandia National Laboratories (SNL), Albuquerque, NM, and Livermore, CA (United States)
OSTI Identifier:
879980
Patent Number(s):
6858943
Application Number:
10/396879
Assignee:
Sandia Corporation (Albuquerque, NM)
Patent Classifications (CPCs):
B - PERFORMING OPERATIONS B81 - MICROSTRUCTURAL TECHNOLOGY B81B - MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
B - PERFORMING OPERATIONS B82 - NANOTECHNOLOGY B82Y - SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES
DOE Contract Number:  
AC04-94AL85000
Resource Type:
Patent
Country of Publication:
United States
Language:
English

Citation Formats

Peterson, Kenneth A, Garrett, Stephen E, and Reber, Cathleen A. Release Resistant Electrical Interconnections For Mems Devices. United States: N. p., 2005. Web.
Peterson, Kenneth A, Garrett, Stephen E, & Reber, Cathleen A. Release Resistant Electrical Interconnections For Mems Devices. United States.
Peterson, Kenneth A, Garrett, Stephen E, and Reber, Cathleen A. Tue . "Release Resistant Electrical Interconnections For Mems Devices". United States. https://www.osti.gov/servlets/purl/879980.
@article{osti_879980,
title = {Release Resistant Electrical Interconnections For Mems Devices},
author = {Peterson, Kenneth A and Garrett, Stephen E and Reber, Cathleen A},
abstractNote = {A release resistant electrical interconnection comprising a gold-based electrical conductor compression bonded directly to a highly-doped polysilicon bonding pad in a MEMS, IMEMS, or MOEMS device, without using any intermediate layers of aluminum, titanium, solder, or conductive adhesive disposed in-between the conductor and polysilicon pad. After the initial compression bond has been formed, subsequent heat treatment of the joint above 363 C creates a liquid eutectic phase at the bondline comprising gold plus approximately 3 wt % silicon, which, upon re-solidification, significantly improves the bond strength by reforming and enhancing the initial bond. This type of electrical interconnection is resistant to chemical attack from acids used for releasing MEMS elements (HF, HCL), thereby enabling the use of a "package-first, release-second" sequence for fabricating MEMS devices. Likewise, the bond strength of an Au--Ge compression bond may be increased by forming a transient liquid eutectic phase comprising Au-12 wt % Ge.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2005},
month = {2}
}