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:
Jun. 01, 2010
Filed:
Jul. 22, 2009
Mengyu Pan, Shanghai, CN;
Zengyi He, Shanghai, CN;
Kaiyu Chen, Shanghai, CN;
Alpha & Omega Semiconductor, Ltd., Hamilton, BM;
Abstract
A device structure is disclosed for preventing gate oxide damage of a trench MOSFET during wafer processing while adding an ESD protection module atop the trench MOSFET. The ESD protection module has a low temperature oxide (LTO) bottom layer whose patterning process was found to cause the gate oxide damage before. The present invention structure includes a semiconductor substrate having an active area and a termination area; numerous trench MOSFET cells disposed in the active area; numerous electrostatic discharge (ESD) diodes disposed above the semiconductor substrate in the termination area; and an insulation layer comprising Oxide/Nitride/Oxide (ONO) sandwiched between the ESD diodes and the semiconductor substrate. In one embodiment, the active area does not contain the ONO insulation layer.