Microcavity structure and encapsulation structure for a microelectronic device

Method for producing a microcavity structure, comprising at least the steps of:

• producing a portion of sacrificial material on a second substrate;
• producing at least two portions of materials with different thermal expansion coefficients placed one against the other and partially on the portion of sacrificial material so that at least a first end of said two portions is placed on the second substrate and at least a second end of said two portions is placed on the portion of sacrificial material;
• attachment of the second substrate to a first substrate so that a space between the second substrate and the first substrate forms the microcavity;
• producing at least one hole through the second substrate, forming an access to the portion of sacrificial material;
• elimination of the portion of sacrificial material through the hole, said two portions of materials with different thermal expansion coefficients forming a closing flap of the hole so that said two portions are capable of closing or not the hole under the effect of a temperature variation.

Method for producing a microcavity structure, comprising at least the steps of:

• deposition of a layer of sacrificial material on a substrate;
• shaping the layer of sacrificial material;
• producing at least two portions of materials with different thermal expansion coefficients placed one against the other on the layer of sacrificial material;
• producing a portion of sacrificial material placed, in part, on said two portions of materials with different thermal expansion coefficients and on the layer of sacrificial material;
• deposition of a cover layer covering the layer of sacrificial material, said two portions of materials with different thermal expansion coefficients and the portion of the sacrificial material;
• producing at least one hole through the cover layer, forming an access to the portion of sacrificial material;
• elimination of the portion and of the layer of sacrificial material through the hole, forming the microcavity, said two portions of materials with different thermal expansion coefficients forming a closing flap of the hole so that said two portions are capable of closing or not the hole under the effect of a temperature variation.