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:
Dec. 21, 2004
Filed:
Sep. 06, 2002
Sunil D. Mehta, San Jose, CA (US);
Lattice Semiconductor Corporation, Hillsboro, OR (US);
Abstract
A device having electrically isolated low voltage and high voltage substrate regions includes low voltage and high voltage trench isolation structures in which a deep portion of the high voltage isolation trench provides electrical isolation in the high voltage regions. The high voltage isolation trench structures include a shallow portion that is simultaneously formed with the low voltage trench isolation structures. The deep portion of the high voltage isolation trench has a bottom surface and shares a continuous wall surface with the shallow portion that extends from the bottom surface to the principal surface of the substrate. A process for fabricating the device includes the use of a single resist pattern to simultaneously form the low voltage isolation trench structures and the shallow portion of the high voltage isolation structures.