Back to results
US 4,283,236 AGranted
Method of fabricating lateral PNP transistors utilizing selective diffusion and counter doping
AssigneeHarris Corporation
InventorRamesh M. Sirsi
Life of this patent
Estimating the term…
Abstract
A lateral PNP transistor is formed by diffusing N type inpurities into an N type layer to form base contact region and base region, diffusing P type impurities into the N base region and N layer to form emitter and collector regions respectively, and counter doping the layer area between the N base region and the collector region. The counter doping is performed through a non-critical mask aperture extending between the emitter and collector regions.
Claims11
A method of fabricating lateral PNP transistors comprising:
- introducing N type impurities into a low impurity concentration N type base region to form high impurity concentration N type base and base contact regions;
- introducing P type impurities into said low impurity concentration base region to form P type collector region and into said high impurity concentration base region to form P type emitter region;
- and
- introducing P type impurities into the region between said collector and emitter regions of sufficient concentration to counter dope the low impurity concentration base region between said collector region and said high impurity concentration base region without converting said high impurity concentration base region.
1 more element
A method of fabricating lateral PNP transistors comprising:
- forming a mask layer on an N type with base contact, emitter and collector apertures in said mask layer;
- introducing N type impurities through said base contact and emitter apertures to form a base contact region and base region of higher impurity concentration than said layer;
- introducing P type impurities through said emitter and collector apertures to form an emitter region in said base region and collector region in said layer;
- removing portion of said mask layer between said emitter and collector apertures;
- and
- introducing P type impurties into the region between said emitter and collector regions of sufficient concentration to counter dope the portion of said layer between said collector region and said base region without converting said base region.
3 more elements
Dependencies are inferred from the claim text.