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. 01, 2001
Filed:
Oct. 15, 1999
Chia-Chen Liu, Hsinchu, TW;
Abstract
The present invention discloses an EPLD cell includes a semiconductor substrate, tunnel buried layer, control gate, and floating gate. The tunnel buried layer and control gate, which has a three-dimensional contour, are formed under the surface of semiconductor substrate by implanting N-type dopant. The floating gate formed completely over the tunnel buried layer and partially over the control gate, is insulating from them by oxide layers. Because of the three-dimensional contour of control gate, the overlapped area between the floating gate and control gate could be increase without expanding horizontal area of the cell. Therefore, the efficiency of the cell can be improved without degrading the integration in applying the cell.