Highly sensitive resonant force sensor with a test body and at least one resonant element decoupled and each disposed in a suitable environment

A force sensor comprising:

• a support,
• a test body hanging to the support,
• at least one strain gauge,
• mechanical transmission means between the test body and the at least one strain gauge so that a movement of the test body applies a strain onto the at least one strain gauge in a first direction of the plane of the sensor, the transmission means being hinged relative to the support about a second direction in the plane of the sensor, the test body being accommodated within a first volume, the at least one strain gauge being accommodated within a second volume and being movable in the second volume, the first volume and the second volume being tightly insulated from each other by a sealed insulation,
• wherein the sensor includes, in that order, a thick substrate, a sacrificial layer over the substrate, a nanometric layer, a protective layer and a micrometric layer,
• wherein the test body and at least one portion of the support are formed in the substrate,
• wherein the sealed insulation is partially formed by the nanometric layer and by the sacrificial layer, and
• wherein the at least one strain gauge is formed in the nanometric layer, wherein the first volume is at a first pressure and the second volume is at a second pressure, the first pressure being higher than the second pressure.