Method of producing suspended elements for electrical connection between two portions of a micromechanism which can move relative to one another
AssigneeSTMicroelectronics S.r.l.
InventorsBruno Murari, Benedetto Vigna, Ubaldo Mastromatteo
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Abstract
A method of producing suspended elements for electrical connection between two portions of a micro-mechanism that can move relative to one another provides for the formation of a layer of sacrificial material, the formation of the electrical connection elements on the layer of sacrificial material, and the selective removal of the layer of sacrificial material beneath the electrical connecting elements, the layer of sacrificial material being a thin film with at least one adhesive side that can be applied dry to the surface of the micro-mechanism.
Claims14
A method of producing suspended elements between two portions of a micro-mechanism containing components that move relative to one another on a semiconductor wafer, the method comprising:
- applying the adhesive side of a dry film over the micro-mechanism on the semiconductor wafer to immobilize the moveable components without penetrating any cavities therein;
- forming a mask on the dry film;
- depositing, developing, and selectively removing a sacrificial layer from the mask and the dry film to form windows on the dry film, the dry film protecting the cavities from infiltration of liquids during the developing step;
- opening the windows by selectively etching the dry film;
- depositing a dielectric layer to cover the windows without penetrating any underlying cavities;
- depositing a conductive layer that is attached to at least one moveable portion of the micro-mechanism;
- and
- selectively removing the conductive layer and the dielectric layer, and removing the dry film to form electrical connection elements suspended between the two portions of the micro-mechanism containing components that move relative to one another.
Dependencies are inferred from the claim text.