US 12,341,012 B2
Method for annealing a gate insulation layer on a wide band gap semiconductor substrate
Thomas Aichinger, Faak am See (AT); Gerald Rescher, Bruckl (AT); and Michael Stadtmueller, Villach (AT)
Assigned to Infineon Technologies AG, Neubiberg (DE)
Filed by Infineon Technologies AG, Neubiberg (DE)
Filed on Feb. 8, 2022, as Appl. No. 17/666,654.
Application 17/666,654 is a continuation of application No. 16/374,457, filed on Apr. 3, 2019, granted, now 11,295,951.
Claims priority of application No. 102018107966.4 (DE), filed on Apr. 4, 2018.
Prior Publication US 2022/0157607 A1, May 19, 2022
Int. Cl. H01L 21/28 (2025.01); H01L 21/02 (2006.01); H01L 21/04 (2006.01); H10D 12/01 (2025.01); H10D 30/60 (2025.01); H10D 62/17 (2025.01); H10D 62/832 (2025.01); H10D 64/01 (2025.01)
CPC H01L 21/049 (2013.01) [H01L 21/02164 (2013.01); H01L 21/02271 (2013.01); H01L 21/02337 (2013.01); H10D 12/031 (2025.01); H10D 30/60 (2025.01); H10D 62/235 (2025.01); H10D 62/8325 (2025.01); H10D 64/01 (2025.01)] 23 Claims
OG exemplary drawing
 
1. A method for forming a wide band gap semiconductor device, the method comprising:
forming a gate insulation layer on a wide band gap semiconductor substrate;
performing a first annealing process during which the gate insulation layer is annealed using at least a first reactive gas species, wherein the first annealing process is performed in a reactive gas atmosphere comprising at least 0.1 vol % of the first reactive gas species and at most 0.1 vol % of the second reactive gas species;
performing a second annealing process separate from the first annealing process and during which the gate insulation layer is annealed using at least a second reactive gas species, wherein the second annealing process is performed in a reactive gas atmosphere comprising at least 0.1 vol % of the second reactive gas species and at most 0.1 vol % of the first reactive gas species;
diluting the first reactive gas species with an inert gas so that a volume percent of the first reactive gas species is at least 1 vol % and at most 50 vol %; and
annealing the gate insulation layer in an inert gas atmosphere,
wherein the first reactive gas species differs from the second reactive gas species,
wherein the first reactive gas species is nitric oxide.