The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 22, 2005
Filed:
Mar. 25, 2003
Kenneth A. Peterson, Albuquerque, NM (US);
Stephen E. Garrett, Albuquerque, NM (US);
Cathleen A. Reber, Corrales, NM (US);
Kenneth A. Peterson, Albuquerque, NM (US);
Stephen E. Garrett, Albuquerque, NM (US);
Cathleen A. Reber, Corrales, NM (US);
Sandia Corporation, Albuquerque, NM (US);
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.