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. 29, 2007
Filed:
Feb. 13, 2004
Yoshitaka Nakamura, Tokyo, JP;
Hidekazu Goto, Tokyo, JP;
Isamu Asano, Tokyo, JP;
Mitsuhiro Horikawa, Tokyo, JP;
Keiji Kuroki, Tokyo, JP;
Hiroshi Sakuma, Tokyo, JP;
Kenichi Koyanagi, Tokyo, JP;
Tsuyoshi Kawagoe, Tokyo, JP;
Yoshitaka Nakamura, Tokyo, JP;
Hidekazu Goto, Tokyo, JP;
Isamu Asano, Tokyo, JP;
Mitsuhiro Horikawa, Tokyo, JP;
Keiji Kuroki, Tokyo, JP;
Hiroshi Sakuma, Tokyo, JP;
Kenichi Koyanagi, Tokyo, JP;
Tsuyoshi Kawagoe, Tokyo, JP;
Elpida Memory, Inc., Tokyo, JP;
Hitachi ULSI Systems, Co., Ltd., Tokyo, JP;
Hitachi Ltd., Tokyo, JP;
Abstract
A semiconductor device includes memory cells each having an MISFET for memory selection formed on one major surface of a semiconductor substrate and a capacitive element comprised of a lower electrode electrically connected at a bottom portion to one of a source and drain of the MISFET for memory selection via a first metal layer and an upper electrode formed on the lower electrode via a capacitive insulating film. The lower electrode has a thickness of 30 nm or greater at the bottom portion thereof. Sputtering with a high ionization ratio and high directivity, such as PCM, is adapted to the formation of the lower electrode to make only the bottom portion of a capacitor thicker.