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:
Apr. 26, 1988
Filed:
Jan. 30, 1987
Peter J Zdebel, Mesa, AZ (US);
Raymond J Balda, Tempe, AZ (US);
Motorola Inc., Schaumburg, IL (US);
Abstract
A process is disclosed for fabricating improved integrated circuit devices. In accordance with one embodiment of the invention integrated devices are fabricated by a four layer poly process which produces small device areas without relying upon restrictive photolithography tolerances. A master mask is used to define the basic footprint of the device in combination with easy to align block-out masks in each lithography step. A double implant doping process is used to control the Gummel number in the base of bipolar transistors and like regions. A shallow implant is placed in a screen oxide and a deep implant into the desired base location. The dopant saturated screen oxide prevents segregation of the deep base implant during subsequent heat treatment. The double implant process applies to many desired device structures.