Anodizing apparatus and anodizing method therefor

An anodizing apparatus that applies voltage between an cathode and a substrate to perform an anodizing process on a treatment surface of the substrate, the anodizing apparatus comprising:

• a container having an opening at a position facing the substrate, the opening covered by an electrolyte membrane with an electrolytic solution contained in the container;
• a cathode disposed inside of the container at a position facing the electrolyte membrane;
• a power supply that applies voltage between the cathode and the substrate;
• and
• a mount base on which the substrate is placed, the mount base being disposed at a position facing the cathode with the electrolyte membrane interposed therebetween,
• wherein the electrolyte membrane has a contact region that contacts the treatment surface of the substrate and a peripheral region that faces the mount base so as to surround the contact region, and
• wherein, a surface of the mount base facing the peripheral region is made of insulating material.