Substrate bonding device, calculation device, substrate bonding method, and calculation method

A substrate bonding apparatus comprising:

• a first holder configured to hold a first substrate;
• and
• a second holder configured to hold a second substrate,
• wherein the substrate bonding apparatus is configured to bond the first substrate and the second substrate by;
• forming a contact region between a part of the first substrate and a part of the second substrate;
• after forming the contact region, expanding the contact region so as to form an initially bonded region set based on information of distortion of the second substrate by maintaining a holding of an outer part of the second substrate by the second holder until the initially bonded region is formed;
• and
• after forming the initially bonded region, releasing an outate part of the second substrate from the second holder,
• wherein the second holder includes:
• an adsorbing portion configured to adsorb at least an outer circumferential portion of the second substrate;
• and
• a protruding portion configured to protrude toward the second substrate for pressing and deforming a center portion of the second substrate, and
• wherein a protruding amount of the protruding portion is variable,
• wherein the protruding portion is detachable, and
• wherein the protruding portion includes a plurality of protruding portions and the protruding amount is variable by exchanging the plurality of protruding portions having different heights.