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. 10, 1998
Filed:
Oct. 31, 1996
James Tajadod, Dedham, MA (US);
Timothy Edward Boles, Tyngsboro, MA (US);
Paulette Rita Noonan, Dracut, MA (US);
The Whitaker Corporation, Wilmington, DE (US);
Abstract
A method of fabricating a bipolar junction transistor having emitter line spacings on the order of approximately 0.25 microns or less is disclosed. Windows are opened in the silicon dioxide layer for the emitter collector and base fabrication. A layer of silicon nitride is disposed on top of the layer of silicon dioxide having been deposited over he entire surface containing approximately 0.5 width line features at he emitter, base and collector sites. Silicon nitride is deposited by low pressure chemical vapor deposition (LPCVD). The deposited nitride film is etched using a standard reactive ion etching technique, removing the silicon nitride from the horizontal surfaces of the oxide without removing the nitride from the sidewalls of the etched opening at the emitter, base and collector sites. The result of the RIE etching is that the thickness of the film on the horizontal surfaces is removed without removal of the nitride from the sidewalls of the etched pattern. The resulting spacer produces the window of the original features at the emitter, base and collector by a dimension of approximately 2X the thickness of the deposited silicon nitride.