Abstract: Atomic diffusion bonding is carried out using a bonding film comprising a nitride formed at a bonding surface. Operating in a vacuum chamber, a bonding film comprising a nitride is formed on each of flat surfaces of two substrates that each have the flat surface, and, by overlapping the two substrates so the bonding films formed on the two substrates are in contact with each other, the two substrates are joined by the generation of atomic diffusion at a bonding interface between the bonding films.

Abstract: A bonded structure includes a first substrate; a second substrate placed opposite to the first substrate; an intermediate layer provided between the first substrate and the second substrate and including a first oxide thin film layered on the first substrate and a second oxide thin film layered on the second substrate; either or both of the first oxide thin film and the second oxide thin film of the intermediate layer being formed of oxide thin films having increased defects; and an interface between the first oxide thin film and the second oxide thin film=being bonded by chemical bonding, and the interface comprising a low-density portion whose density is lower than that of the two oxide thin films.

Abstract: A bonded structure includes a first substrate; a second substrate placed opposite to the first substrate; an intermediate layer provided between the first substrate and the second substrate and including a first oxide thin film layered on the first substrate and a second oxide thin film layered on the second substrate; either or both of the first oxide thin film and the second oxide thin film of the intermediate layer being formed of oxide thin films having increased defects; and an interface between the first oxide thin film and the second oxide thin film=being bonded by chemical bonding, and the interface comprising a low-density portion whose density is lower than that of the two oxide thin films.

Abstract: The present invention achieves chemical bonding by means of a joined film made of oxides formed on a joined surface. In a vacuum container, amorphous oxide thin films are respectively formed on smooth surfaces of two substrates, and the two substrates overlap such that the amorphous oxide thin films formed on the two substrates come into contact with each other, thereby causing chemical bonding involving an atomic diffusion at a joined interface between the amorphous oxide thin films to join the two substrates.