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. 25, 2003
Filed:
Jun. 03, 1999
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A semiconductor device—which includes surface-type n-channel and p-channel single gate transistors by formation of fixed charges within a gate oxide film—and a manufacturing method therefor. A voltage is applied between an electrode connected to a gate electrode and an electrode connected to an N region formed in an n-well, and electrons are implanted into the gate electrode at high energy from a substrate, thereby producing fixed negative electric charges in a gate oxide film within an range of 1E11 cm to 1E14 cm . An appropriate value for Vth is obtained in the surface channel MOSFET. Therefore, there are solved problems associated with a dual gate structure; namely, a complicated process flow, etch residues or excessive etching due to a difference in etch rate between n-type polycrystalline silicon and p-type polycrystalline silicon, and the deterioration of a gate oxide film due to penetration of boron ions.