Abstract: A process assembling first and second substrates on contact faces by molecular bonding. The first substrate contact face has an electrically conducting layer on at least part of its surface. The process deposits a bond layer on at least part of the electrically conducting layer, which bond layer can molecularly bond with a zone of the second substrate contact face and be combined with the electrically conducting layer to form a conducting alloy, contacts the bond layer with the zone of the second substrate contact face and molecularly bond them, and transforms over all or part of its thickness of all or part of the electrically conducting layer with all or part of the bond layer and with at least part of the thickness of the zone of the contact face on all or part of the surface of the second substrate to form a conducting alloy(s) zone.

Abstract: A semiconductor heterostructure laser cavity is disclosed which has semiconductor layers epitaxied to define four zones on a substrate. The laser cavity includes a first zone with a composition that varies continuously from a first face to a second face with a gap decreasing from the first face to the second face, the first zone ensuring an optical confinement and light guidance. A second zone constitutes an active emission zone in contact with the second face of the first zone and having at least one quantum well with a gap smaller than that of the first zone. A third zone has a gap larger than that of the at least one quantum well. The third zone ensuring an optical confinement and a light guidance, and having a composition which varies continuously from a first face to a second face with a gap which increases from the first face to the second face, the first face of the third zone being in contact with the active emission zone.