US 11,888,037 B2
Self-aligned field plate mesa FPM SiC schottky barrier diode
Andrei Mihaila, Rieden (CH); Lars Knoll, Hägglingen (CH); and Lukas Kranz, Zürich (CH)
Assigned to Hitachi Energy Ltd, Zurich (CH)
Appl. No. 16/978,560
Filed by Hitachi Energy Ltd, Zurich (CH)
PCT Filed Mar. 5, 2019, PCT No. PCT/EP2019/055376
§ 371(c)(1), (2) Date Sep. 4, 2020,
PCT Pub. No. WO2019/170631, PCT Pub. Date Sep. 12, 2019.
Claims priority of application No. 18160331 (EP), filed on Mar. 6, 2018.
Prior Publication US 2021/0020753 A1, Jan. 21, 2021
Int. Cl. H01L 29/06 (2006.01); H01L 29/40 (2006.01); H01L 29/16 (2006.01); H01L 29/20 (2006.01); H01L 29/66 (2006.01); H01L 29/861 (2006.01); H01L 29/872 (2006.01)
CPC H01L 29/407 (2013.01) [H01L 29/0649 (2013.01); H01L 29/0661 (2013.01); H01L 29/1608 (2013.01); H01L 29/2003 (2013.01); H01L 29/6606 (2013.01); H01L 29/66143 (2013.01); H01L 29/8613 (2013.01); H01L 29/872 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A power semiconductor device comprising:
a wide-bandgap semiconductor layer having a first main side and a second main side opposite to the first main side, wherein the first main side and the second main side extend in a lateral direction and wherein the wide-bandgap semiconductor layer comprises an active region and a termination region that laterally surrounds the active region, wherein the wide-bandgap semiconductor layer has a first recess that is recessed from the first main side in the termination region and surrounds the active region and wherein the wide-bandgap semiconductor layer also has a second recess that is recessed from the first main side in the active region and is filled with an insulating material, a depth of the second recess being the same as a depth of the first recess;
a field plate on the first main side of the wide-bandgap semiconductor layer over a first portion of the termination region, the field plate exposing the active region and a second portion of the wide-bandgap semiconductor layer in the termination region; and
a dielectric layer interposed between the field plate and the wide-bandgap semiconductor layer to separate the field plate from the wide-bandgap semiconductor layer;
wherein a sidewall of the first recess adjacent to the active region is laterally aligned with a circumferential edge of the field plate such that in an orthogonal projection onto a plane parallel to the first main side, an edge of the first recess defined by an upper end of the sidewall is within less than 1 nm from the circumferential edge of the field plate.