US 12,224,329 B2
Trench transistor
Christian Tobias Banzhaf, Laichingen (DE); Jan-Hendrik Alsmeier, Pfullingen (DE); Stephan Schwaiger, Bodelshausen (DE); Wolfgang Feiler, Reutlingen (DE); Dick Scholten, Stuttgart (DE); and Klaus Heyers, Reutlingen (DE)
Assigned to ROBERT BOSCH GMBH, Stuttgart (DE)
Appl. No. 17/635,823
Filed by Robert Bosch GmbH, Stuttgart (DE)
PCT Filed Aug. 24, 2020, PCT No. PCT/EP2020/073626
§ 371(c)(1), (2) Date Apr. 12, 2022,
PCT Pub. No. WO2021/037794, PCT Pub. Date Mar. 4, 2021.
Claims priority of application No. 10 2019 212 646.4 (DE), filed on Aug. 23, 2019.
Prior Publication US 2022/0320306 A1, Oct. 6, 2022
Int. Cl. H01L 29/423 (2006.01); H01L 29/16 (2006.01); H01L 29/78 (2006.01)
CPC H01L 29/42368 (2013.01) [H01L 29/4236 (2013.01); H01L 29/4238 (2013.01); H01L 29/1608 (2013.01); H01L 29/7827 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A trench transistor, comprising:
a semiconductor region;
a trench structure formed in the semiconductor region;
a gate insulation layer and an electrically conductive gate layer formed on the gate insulation layer in the trench structure; and
a gate contact, which is electrically conductively connected to the electrically conductive gate layer in an edge area of the trench transistor, a thickness of the gate insulation layer in the edge area of the trench transistor being greater than a thickness in an active area of the trench transistor,
wherein a width of the trench structure increases continuously from the active area of the trench transistor to the edge area of the trench transistor.