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:
Feb. 24, 1987
Filed:
Dec. 31, 1984
Charles L Vinn, Milpitas, CA (US);
David J Harris, San Jose, CA (US);
Raytheon Company, Lexington, MA (US);
Abstract
A subsurface Zener diode is provided wherein a semiconductor has formed thereon spaced apart anode and cathode regions of opposite type conductivity, such regions having opposing surface portions, and disposed beneath a surface of such semiconductor a buried region of conductivity type the same as one of such regions, such buried region extending laterally through the spaced apart regions, one of the spaced apart regions having an opposing surface portion thereof formed with a portion which protrudes towards the opposing surface portion of the other one of the spaced apart regions. With such arrangement, an electric field produced between the spaced apart regions becomes concentrated at the protrusion with the result that Zener breakdown occurs repeatedly at the same point in the semiconductor thereby reducing long term drift. Also, a Kelvin buried Zener diode is provided by forming a second laterally spaced anode region with the cathode region disposed between the pair of anode regions. One of the pair of anodes provides the force anode and the other the sense anode. The buried region extends laterally through the pair of anodes and the cathode region. The cathode region is provided with the portion which protrudes towards the force anode of the pair of anode regions and such cathode is elongated along an axis which passes between the pair of force and sense anode regions. The elongated cathode thus improves isolation between the force and sense anodes.