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:
Sep. 10, 1991
Filed:
Aug. 14, 1989
Mitsuo Yasuhira, Ikeda, JP;
Takatoshi Yasui, Higashiosaka, JP;
Kazuhiro Matsuyama, Neyagawa, JP;
Hideyuki Iwata, Hirakata, JP;
Masanori Fukumoto, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A semiconductor memory device includes a capacitor and an insulating separation area in a trench formed around a switching transistor, with a storage electrode of the capacitor being sandwiched between an upper and a lower cell plate electrode to reduce leakage current due to the parasitic MOS transistor effect in the trench sidewall along the channel in the switching transistor and leakage current due to the gate-controlled diode effect in the trench sidewall. Also, a method is disclosed for manufacturing such semiconductor memory device.