US 12,392,053 B2
Group 13 element nitride crystal layer, self-supporting substrate, and functional element
Suguru Noguchi, Nagoya (JP); Takayuki Hirao, Toyota (JP); Yoshinori Isoda, Ichinomiya (JP); and Tetsuya Uchikawa, Nagoya (JP)
Assigned to NGK INSULATORS, LTD., Nagoya (JP)
Filed by NGK INSULATORS, LTD., Nagoya (JP)
Filed on May 18, 2022, as Appl. No. 17/747,501.
Application 17/747,501 is a continuation of application No. PCT/JP2020/027467, filed on Jul. 15, 2020.
Claims priority of application No. 2019-210396 (JP), filed on Nov. 21, 2019.
Prior Publication US 2022/0275532 A1, Sep. 1, 2022
Int. Cl. C30B 29/40 (2006.01); C30B 19/02 (2006.01); C30B 25/18 (2006.01); H10D 62/85 (2025.01); H10H 20/825 (2025.01)
CPC C30B 29/406 (2013.01) [C30B 19/02 (2013.01); C30B 25/18 (2013.01); H10D 62/8503 (2025.01); H10H 20/825 (2025.01)] 14 Claims
OG exemplary drawing
 
1. A group 13 nitride crystal layer comprising a group 13 nitride crystal selected from gallium nitride, aluminum nitride, indium nitride or the mixed crystals thereof, said group 13 nitride crystal layer comprising an upper surface and bottom surface,
wherein said group 13 nitride crystal layer comprises high-luminance layers and low-luminance layers, each high-luminance layer being a layer that has a brightness higher side when observed by cathode luminescence and each low-luminance layer being a layer that has a brightness lower side when observed by cathode luminescence, the high-luminance layers and low-luminance layers being present alternately and wherein each said low-luminance layer has a thickness of between 3 times and 10 times of a thickness of each said high-luminance layer, wherein each said high-luminance layer comprises an n-type dopant or a p-type dopant and each said low-luminance layer comprises an n-type dopant or a p-type dopant in a lesser amount with respect to the high-luminance layers.