US 11,908,927 B2
Nitride semiconductor device
Hirotaka Otake, Kyoto (JP); Shinya Takado, Kyoto (JP); and Kentaro Chikamatsu, Kyoto (JP)
Assigned to ROHM CO., LTD., Kyoto (JP)
Appl. No. 17/433,146
Filed by ROHM CO., LTD., Kyoto (JP)
PCT Filed Jan. 23, 2020, PCT No. PCT/JP2020/002354
§ 371(c)(1), (2) Date Aug. 23, 2021,
PCT Pub. No. WO2020/174956, PCT Pub. Date Sep. 3, 2020.
Claims priority of application No. 2019-036271 (JP), filed on Feb. 28, 2019.
Prior Publication US 2022/0181477 A1, Jun. 9, 2022
Int. Cl. H01L 29/778 (2006.01); H01L 29/20 (2006.01); H01L 29/205 (2006.01); H01L 29/40 (2006.01); H01L 29/423 (2006.01); H01L 29/66 (2006.01)
CPC H01L 29/7786 (2013.01) [H01L 29/2003 (2013.01); H01L 29/205 (2013.01); H01L 29/401 (2013.01); H01L 29/42316 (2013.01); H01L 29/66462 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A nitride semiconductor device comprising: a first nitride semiconductor layer that constitutes an electron transit layer;
a second nitride semiconductor layer that is formed on the first nitride semiconductor layer and constitutes an electron supply layer;
a nitride semiconductor gate layer that is disposed on the second nitride semiconductor layer, has a ridge portion at least at a portion thereof, and contains an acceptor type impurity;
a gate electrode that is disposed at least on the ridge portion of the nitride semiconductor gate layer;
a source electrode that is disposed on the second nitride semiconductor layer and has a source principal electrode portion parallel to the ridge portion; and
a drain electrode that is disposed on the second nitride semiconductor layer and has a drain principal electrode portion parallel to the ridge portion; and
wherein a length direction of the ridge portion is a [110] direction of a semiconductor crystal structure that constitutes the second nitride semiconductor layer.