Method for producing a structure comprising a mobile element by means of a heterogeneous sacrificial layer

A method for producing a structure on a substrate successively comprising:

• depositing a second sacrificial material;
• depositing a first sacrificial material, the first sacrificial material being different from the second sacrificial material;
• after depositing the second and first sacrificial materials, patterning the first sacrificial material to form a first pad of first sacrificial material on the second sacrificial material and then patterning the second sacrificial material to form a second pad of second sacrificial material, so that the first pad of first sacrificial material is arranged on a top surface of the second pad of second sacrificial material, the top surface of the second pad having a free surface around the first pad;
• depositing an active layer made of a first material, the active layer covering at least a whole of side walls of the first and second pads and said surface around the first pad;
• patterning the active layer to allow access to the first pad;
• removing the first pad so as to release a free area of the active layer, the free area being secured to the substrate by a securing area made of the active layer;
• and
• removing the second pad after the first pad has been removed to access the substrate.

A method for producing a structure on a substrate successively comprising:

• providing the substrate with a first pattern of first sacrificial material and a second pattern of second sacrificial material, the first pattern being separated from the substrate by the second pattern, the first and second patterns presenting sidewalls connecting a top face of the pattern with a bottom face of the pattern, the first pattern defining an annular area devoid of the first sacrificial material on a top face of the second pattern around the first pattern and extending from the sidewalls of the first pattern to the sidewalls of the second pattern;
• depositing an active layer so as to cover the sidewalls of the first and second patterns, the annular area and the top face of the first pattern;
• patterning the active layer to access the first pattern, the annular area and the sidewalls of the second pattern being covered by the active layer;
• removing the first sacrificial material selectively versus the second sacrificial material so as to release a free area of the active layer, the free area being secured to the substrate by a securing area made of the active layer;
• and
• removing the second sacrificial material after the first sacrificial material has been removed.