US 12,294,019 B2
Method for manufacturing nitride semiconductor device and nitride semiconductor device
Ryo Tanaka, Tokyo (JP); Yuki Ohuchi, Tokyo (JP); Katsunori Ueno, Nagano (JP); and Shinya Takashima, Tokyo (JP)
Assigned to FUJI ELECTRIC CO., LTD., Kawasaki (JP)
Filed by FUJI ELECTRIC CO., LTD., Kawasaki (JP)
Filed on Jan. 24, 2022, as Appl. No. 17/582,710.
Claims priority of application No. 2021-36613 (JP), filed on Mar. 8, 2021.
Prior Publication US 2022/0285503 A1, Sep. 8, 2022
Int. Cl. H01L 29/20 (2006.01); H01L 21/02 (2006.01); H01L 21/265 (2006.01)
CPC H01L 29/2003 (2013.01) [H01L 21/02389 (2013.01); H01L 21/26546 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A method for manufacturing a nitride semiconductor device comprising:
forming N-type regions in a nitride semiconductor layer;
implanting ions of an acceptor element into a region sandwiched by the N-type regions on both sides in the nitride semiconductor layer; and
forming a P-type region sandwiched by the N-type regions on both sides by subjecting the nitride semiconductor layer in which the N-type regions are formed and into which ions of the acceptor element are implanted to heat treatment and activating the acceptor element,
wherein, in the forming the N-type regions,
the method implants ions of a donor element to the nitride semiconductor layer at a high concentration in such a way that concentration of the donor element in the N-type regions has a value equal to or greater than concentration of the acceptor element in the P-type region, and
in the implanting ions of the acceptor element,
the method implants ions of the acceptor element in such a way that:
concentration of the acceptor element in the P-type region is 1×1019 cm−3 or more and 1×1021 cm−3 or less; and
a region into which the ions of the acceptor element is implanted partially overlaps the N-type regions adjacent to the P-type region, and
the P-type region includes:
a first region; and
second regions each of which is located between the first region and one of the N-type regions and is respectively in contact with the first region and the N-type region, wherein
concentration of the acceptor element in the second regions is higher than in the first region, and
concentration of the acceptor element in the second regions is 1×1019 cm−3 or more and 1×1021 cm−3 or less.