Sensor element, gas sensor, and method for manufacturing sensor element

A sensor element having a laminate structure, and extending in an axial direction, the sensor element comprising:

• a first ceramic layer and a second ceramic layer disposed apart from each other in a laminating direction;
• a third ceramic layer intervening between the first ceramic layer and the second ceramic layer in the laminating direction and having a hollow space formed therein;
• and
• an internal space which is the hollow space surrounded by the first ceramic layer, the second ceramic layer, and the third ceramic layer,
• wherein, at a periphery of the internal space, a fourth ceramic layer containing as a main component a ceramic material different from a ceramic material contained as a main component in the first ceramic layer and the third ceramic layer intervenes between the first ceramic layer and the third ceramic layer which are exposed to the internal space,
• wherein the fourth ceramic layer is a porous layer and has air permeability, and
• wherein, at the periphery of the internal space, a fifth ceramic layer containing as a main component a ceramic material different from the ceramic material contained as the main component in the second ceramic layer and the third ceramic layer intervenes between the second ceramic layer and the third ceramic layer exposed to the internal space.