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:
Nov. 14, 1989
Filed:
Jan. 11, 1988
Isamu Yuito, Hachiouji, JP;
Eijin Moriwaki, Hachiouji, JP;
Kazuo Shiiki, Kanagawa, JP;
Yoshihiro Hamakawa, Koganei, JP;
Hisashi Takano, Hachiouji, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a thin film magnetic head of the type wherein a lower magnetic pole, a gap layer, a first insulating layer, a coil, a second insulating layer and an upper magnetic pole are formed sequentially on a substrate, the present invention provides a thin film magnetic head characterized in that a surface active layer made of aluminum oxide, for example, is disposed between the first insulating layer and the second insulating layer except where the coil is formed on the first insulating layer so that the surface active layer is disposed between the coil and the second insulating layer. According to the present invention, it is possible to prevent the occurrence of bubbles between coil conductors, and eventually to improve flatness of the surface of the second insulating layer and to prevent degradation of the characteristics of the upper magnetic pole.