US 12,278,109 B2
Etching apparatus and etching method
Takayuki Tajima, Sagamihara (JP); Kazuhito Higuchi, Yokohama (JP); Susumu Obata, Yokohama (JP); and Mitsuo Sano, Kamakura (JP)
Assigned to KABUSHIKI KAISHA TOSHIBA, Tokyo (JP)
Filed by KABUSHIKI KAISHA TOSHIBA, Tokyo (JP)
Filed on Mar. 16, 2022, as Appl. No. 17/696,067.
Claims priority of application No. 2021-151998 (JP), filed on Sep. 17, 2021.
Prior Publication US 2023/0091900 A1, Mar. 23, 2023
Int. Cl. H01L 21/306 (2006.01); H01L 21/67 (2006.01)
CPC H01L 21/30608 (2013.01) [H01L 21/67075 (2013.01)] 3 Claims
OG exemplary drawing
 
1. An etching apparatus in which a semiconductor substrate having a first main surface and a second main surface located opposite to the first main surface, a catalyst layer formed on the second main surface of the semiconductor substrate, a first solution capable of dissolving an oxide of a semiconductor substrate material, and a second solution containing an oxidizing agent are to be processed,
the etching apparatus comprising:
a first container configured to store the first solution and including an opening covered by the first main surface of the semiconductor substrate;
a second container configured to store the second solution and including an opening covered by a surface of the catalyst layer;
a first flow path configured to communicate with the first container;
a second flow path configured to communicate with the second container;
a cation exchange film interposed between the first flow path and the second flow path and allowing at least protons to pass through; and
an electric field applier configured to apply an electric field to the semiconductor substrate,
wherein the electric field applier includes a first electrode outside the first container, a second electrode outside the second container, and a direct current power supply whose negative pole is electrically connected to the first electrode and whose positive pole is electrically connected to the second electrode, and
the electric field applier is configured to generate an electric field between the first electrode and the second electrode by the direct current power supply, with the first container, the semiconductor substrate, the catalyst layer, and the second container being provided between the first electrode and the second electrode, and thereby is configured to apply the electric field to the semiconductor substrate.