Bonding system

A bonding system comprising:

• a substrate transfer device configured to transfer a first substrate and a second substrate to a bonding apparatus for bonding the first substrate to the second substrate;
• a first holding plate configured to hold the first substrate from an upper surface side;
• and
• a second holding plate disposed below the first holding plate and configured to hold the second substrate from a lower surface side so that the second substrate faces the first substrate,
• wherein the substrate transfer device includes a first holding part capable of holding the first substrate from the upper surface side, and a second holding part disposed below the first holding part and capable of holding the second substrate from the lower surface side so that the second substrate faces the first substrate, and
• the first holding part and the second holding part are configured to receive the first substrate held by the first holding plate and the second substrate held by the second holding plate at the same time from the first holding plate and the second holding plate, and to hold the first substrate and the second substrate.