US 12,080,790 B2
Power semiconductor devices including angled gate trenches
Woongsun Kim, Cary, NC (US); Daniel Jenner Lichtenwalner, Raleigh, NC (US); Sei-Hyung Ryu, Cary, NC (US); and Naeem Islam, Morrisville, NC (US)
Assigned to Wolfspeed, Inc., Durham, NC (US)
Filed by Wolfspeed, Inc., Durham, NC (US)
Filed on Jul. 23, 2021, as Appl. No. 17/383,696.
Application 17/383,696 is a continuation in part of application No. 17/172,481, filed on Feb. 10, 2021.
Application 17/172,481 is a continuation in part of application No. 17/082,647, filed on Oct. 28, 2020, granted, now 11,610,991.
Prior Publication US 2022/0130998 A1, Apr. 28, 2022
Int. Cl. H01L 29/78 (2006.01); H01L 29/10 (2006.01); H01L 29/40 (2006.01); H01L 29/417 (2006.01)
CPC H01L 29/7813 (2013.01) [H01L 29/1037 (2013.01); H01L 29/407 (2013.01); H01L 29/41741 (2013.01)] 25 Claims
OG exemplary drawing
 
1. A power semiconductor device comprising:
a semiconductor layer structure comprising a drift region that comprises a wide band-gap semiconductor material that has a first conductivity type, a well region that has a second conductivity type, and a source region that has the first conductivity type in an upper portion of the well region;
a gate trench in an upper portion of the semiconductor layer structure and comprising a portion obliquely angled in plan view; and
a gate structure in the gate trench,
wherein the well region is on a side surface of the gate structure, and
wherein the well region comprises an upper outer surface having a parallelogram shape having four interior oblique angles.