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:
Oct. 06, 1998
Filed:
May. 08, 1997
Mike Brenner, Dallas, TX (US);
Timothy J Hogan, Allen, TX (US);
Sean C O'Brien, Plano, TX (US);
Lawrence D Dyer, Richardson, TX (US);
Lisa A Lester, Richardson, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A method of fabricating a monolithic device, preferably a micromechanical device, from a wafer (20) by carefully selecting the composition of two or more layers of photoresist (52,54). The present invention comprises choosing compatible photoresist layers to avoid generating defects in the layers of photoresist which could allow a wet chemical HF acid etch process to damage an underlying micromechanical device. The present invention allows a very strong solution of hydrofluoric acid to be utilized to remove particles and debris after a partial-saw process, and to remove a damaged portion of an underlying CMOS layer (22) at a region (68) proximate a kerf (62). Using an HF solution having a concentration of about 6% is desired. The present invention substantially improves the yield of micromechanical devices.