US 12,268,016 B2
Buried power rail formation for vertical field effect transistors
Ruilong Xie, Niskayuna, NY (US); Junli Wang, Slingerlands, NY (US); Brent A Anderson, Jericho, VT (US); Chen Zhang, Guilderland, NY (US); Heng Wu, Guilderland, NY (US); and Alexander Reznicek, Troy, NY (US)
Assigned to International Business Machines Corporation, Armonk, NY (US)
Filed by International Business Machines Corporation, Armonk, NY (US)
Filed on Dec. 29, 2021, as Appl. No. 17/564,571.
Prior Publication US 2023/0207697 A1, Jun. 29, 2023
Int. Cl. H10D 30/62 (2025.01); H01L 23/522 (2006.01); H01L 23/528 (2006.01); H10D 64/01 (2025.01)
CPC H10D 30/6211 (2025.01) [H01L 23/5226 (2013.01); H01L 23/5286 (2013.01); H10D 64/018 (2025.01)] 20 Claims
OG exemplary drawing
 
10. A semiconductor structure comprising:
a first region including a first channel fin extending vertically above a first bottom source/drain region;
a second region including a second channel fin extending vertically above a second bottom source/drain region, the first region being separated from the second region by an isolation region;
a protective liner along opposite sidewalls of each of the first bottom source/drain region and the second bottom/source drain region, each of the first bottom source/drain region and the second bottom/source drain region located above a semiconductor layer in contact with a first portion of an inner spacer;
a first metal layer located between the first portion of the inner spacer and a second portion of the inner spacer, the first portion of the inner spacer partially covering a top surface of the first metal layer and the second portion of the inner spacer substantially covering a bottom surface of the first metal layer for providing a buried power rail; and
a shallow trench isolation region above an exposed portion of the first metal layer, the shallow trench isolation region being adjacent to the first portion of the inner spacer, the semiconductor layer, and each of the first bottom source/drain region and the bottom source/drain region.