Transducer

A transducer comprising:

• when three axes orthogonal to each other are defined as an X axis, a Y axis, and a Z axis,
• a second semiconductor substrate on which a first insulation layer having a first metal layer on its surface is disposed;
• a first semiconductor substrate that overlaps the second semiconductor substrate in a Z direction extending along the Z axis and on which a second insulation layer having a second metal layer on its surface is disposed;
• a functional element located between the first semiconductor substrate and the second semiconductor substrate;
• and
• a eutectic reaction layer bonding the first semiconductor substrate and the second semiconductor substrate to each other in a bonding region located around the functional element, wherein
• the eutectic reaction layer is a bonding layer formed by eutectic bonding between the first metal layer and the second metal layer,
• at least one of the first insulation layer and the second insulation layer includes a recess having a bottom wider than the bonding region in plan view in the Z direction, and
• the bonding region is located at the bottom.