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. 22, 1983
Filed:
Dec. 04, 1981
Jeremiah P McCarthy, Framingham, MA (US);
Marvin Tabasky, Peabody, MA (US);
GTE Laboratories Incorporated, Waltham, MA (US);
Abstract
Method of fabricating monolithic integrated circuit structure incorporating a bipolar transistor and a high value resistor. First and second N-type sectors are formed in an N-type epitaxial layer by junction isolation. A silicon oxide layer is formed on the surface of the body. The layer is thinner over a part of the first sector and over a part of the second sector. A layer of silicon nitride is formed on portions of the thinner silicon oxide to overlie predetermined zones within each sector. P-type conductivity imparting material is ion implanted through the unprotected thinner silicon oxide to form a low resistivity region in the first sector and two low resistivity regions in the second sector. The layer of silicon nitride overlying the predetermined zone in the second sector is removed, and an opening is formed over the predetermined zone in the second sector. P-type conductivity imparting material is ion implanted through the opening to form a resistor in the predetermined zone of the second sector with the two low resistivity regions providing contact regions at opposite ends thereof. The thickness of the silicon oxide layer is increased except over the predetermined zone of the first sector where it is protected by the remaining silicon nitride layer. The silicon nitride and the underlying silicon oxide are removed exposing the predetermined zone in the first sector. N-type and P-type conductivity imparting materials are ion implanted in the predetermined zone to complete the structure.