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:
Jan. 18, 1977
Filed:
Feb. 18, 1975
Masanobu Hanazono, Hitachi, JA;
Osamu Asai, Hitachi, JA;
Hitachi, Ltd., , JA;
Abstract
A thin film integrated circuit consists of a first conductor of aluminum extended in any desired direction on an insulating substrate, an anodized film formed by anodization in a chromic acid solution at positions other than cross-connectional parts on the first conductor, a second conductor cross-connected on the first conductor, and an anodized film formed by anodization in a chromic acid solution on the surface of the second conductor. The thin film integrated circuit is prepared by partially forming an anodized film in a sulfuric acid or oxalic acid solution at cross-connectional parts of a first conductor of aluminum so as not to form any anodized film in a chromic acid solution at the cross-sectional parts of the first conductor of the circuit, masking the partially formed anodized film with a photoresist film, then forming an anodized film by a chromic acid solution, and then removing the photoresist film and the anodized film. After the cross-sectional parts of the first conductor are exposed thereby, a second conductor is formed. For an etching solution for anodized film, which is anodized using the sulfuric acid or oxalic acid solution, a mixed solution consisting of 60 to 40 g/l of chromic acid and 40 to 300 g/l of oxidative acid is used.