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:
Jul. 31, 2001
Filed:
Jan. 08, 1997
Hidenori Watanabe, Zama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An ink jet head is provided with heaters to generate energy to be utilized for discharging ink, and MOS transistors to supply electric power to the heaters for recording by discharging ink. For this ink jet head, the MOS transistors comprise source regions and drain regions formed by doping layers arranged near the surface of a semiconductor substrate, gates formed on the semiconductor substrate through an oxide film and arranged to cross over the source regions and the drain regions, and contact units formed by a doping layer different from that of the source regions, and arranged near the surface within the source regions in order to draw out electrons or holes to be unintentionally generated on the semiconductor substrate. With the structure thus arranged, the potential difference becomes smaller between the source regions and back gate area on the semiconductor substrate, making it possible to prevent heaters from being destroyed by any excessive current that may flow uncontrollably.