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:
Mar. 03, 1992
Filed:
Jul. 11, 1989
Junichi Mitsuhashi, Hyogo, JP;
Shinichi Satoh, Hyogo, JP;
Hideki Genjyo, Hyogo, JP;
Yoshio Kohno, Hyogo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A high load resistance type static random access memory (SRAM) is provided, as an example of a semiconductor device having a high resistance layer. The SRAM includes a semiconductor substrate (1) of a first conductivity type with an impurity diffusion region (3) of second conductivity type selectively formed thereon. An aluminum interconnection layer (8) is formed over the impurity diffusion region (3). Provided between the aluminum interconnection layer (8) and the impurity diffusion region (3) is a double-layer high resistance structure which comprises a nitride layer (63a) formed adjacent the semiconductor substrate (1) and an oxide layer (63b) adjacent the aluminum interconnection layer (8). The impurity diffusion region (3) forms part of a MOS field effect transistor, which is coupled to the high resistance layer (63) to form a flip-flop memory cell. The double-layer high resistance structure makes it possible to adjust the resistance at a desired particular high value by controlling the thickness of the layer. The structure permits a high degree of integration of the SRAM. The high resistance layer is not affected by diffusion or penetration of the impurity thereto.