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:
May. 29, 2001
Filed:
Dec. 14, 1999
Robert C. Cole, Rancho Palos Verdes, CA (US);
Ruby E. Robertson, Los Angeles, CA (US);
Allyson D. Yarbrough, Hermosa Beach, CA (US);
The Aerospace Corporation, El Segundo, CA (US);
Abstract
A wet and vapor acid etching method releases a microelectromechanical systems (MEMS) structure from a substrate by dissolving a sacrificial layer disposed between the MEMS and the substrate. The sacrificial layer may be a silicon dioxide (SiO,) layer having a field portion over which the MEMS does not extend and a support portion over which the MEMS does extend. The field portion of the SiO,layer is quickly removed using conventional wet hydrofluoric (HF) etching followed by rinsing and drying and then the support portion is removed using conventional vapor HF etching from a solution greater than 45% by weight percent. The wet HF chemical etch quickly removes the large field portion of the sacrificial layer. The HF vapor etch removes the small support portion of the sacrificial layer below the MEMS to release the MEMS from the substrate without stiction thereby preventing damage to the MEMS when released.