US 11,869,958 B2
Heterojunction bipolar transistors
Judson R. Holt, Ballston Lake, NY (US); Shesh Mani Pandey, Saratoga Springs, NY (US); and Vibhor Jain, Williston, VT (US)
Assigned to GLOBALFOUNDRIES U.S. INC., Malta, NY (US)
Filed by GLOBALFOUNDRIES U.S. Inc., Malta, NY (US)
Filed on May 16, 2022, as Appl. No. 17/745,280.
Prior Publication US 2023/0369474 A1, Nov. 16, 2023
Int. Cl. H01L 29/737 (2006.01); H01L 29/66 (2006.01); H01L 29/08 (2006.01); H01L 29/10 (2006.01)
CPC H01L 29/7371 (2013.01) [H01L 29/0804 (2013.01); H01L 29/0821 (2013.01); H01L 29/1004 (2013.01); H01L 29/66242 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A structure comprising:
a collector in a semiconductor substrate;
a subcollector in the semiconductor substrate;
an intrinsic base over the subcollector;
an extrinsic base adjacent to the intrinsic base;
an emitter over the intrinsic base;
an isolation structure between the extrinsic base and the emitter and which overlaps the subcollector; and
a marker layer underneath the extrinsic base and which also covers an upper surface of the emitter.