US 12,249,624 B2
Ohmic contact formation in a SiC-based electronic device
Simone Rascuná, Catania (IT); Mario Giuseppe Saggio, Aci Bonaccorsi (IT); and Giovanni Franco, Viagrande (IT)
Assigned to STMICROELECTRONICS S.R.L., Agrate Brianza (IT)
Filed by STMICROELECTRONICS S.R.L., Agrate Brianza (IT)
Filed on Apr. 8, 2021, as Appl. No. 17/225,998.
Claims priority of application No. 102020000008179 (IT), filed on Apr. 17, 2020.
Prior Publication US 2021/0328022 A1, Oct. 21, 2021
Int. Cl. H01L 29/45 (2006.01); H01L 21/268 (2006.01); H01L 29/16 (2006.01)
CPC H01L 29/1608 (2013.01) [H01L 21/2686 (2013.01); H01L 29/456 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A device, comprising:
a substrate having a first conductivity type and a first surface opposite a second surface;
a plurality of first doped regions each having a second conductivity type and a first surface coplanar with the first surface of the substrate;
a plurality of second doped regions each in a respective one of the plurality of first doped regions, each second doped region having the first conductivity type and a first surface coplanar with the first surface of the respective first doped region;
a first gate on the first surface of the substrate that overlaps a first edge of a first of the plurality of second doped regions and a first edge of a second of the plurality of second doped regions;
a second gate on the first surface of the substrate that overlaps a second edge of the first of the plurality of second doped regions, the second edge being opposite the first edge of the first of the plurality of second doped regions along a first direction;
a metal layer on the first surface of the substrate;
an insulating layer between the metal layer and the first gate, the insulating layer entirely separating the second of the plurality of second doped regions from the metal layer; and
a first ohmic contact between the first gate and the second gate along the first direction, the first ohmic contact being in the first of the plurality of second doped regions, the first ohmic contact having a first surface coplanar with the first surface of the respective first doped region and the first surface of the first of the plurality of second doped regions, and a second surface between the first surface of the substrate and the second surface of the substrate, wherein the first ohmic contact is exclusively surrounded, in a cross-sectional view, by the first of the plurality of second doped regions except for the first surface.