Microbridge structure and method for forming the microbridge structure

Claim 1

A microbridge structure comprising: a substrate layer provided with two first electrical contacts; a microstructure including a sensing area provided with two second electrical contacts; and a micro support for suspending the microstructure over and at a predetermined distance from the substrate layer, the micro support having at least one leg comprising two electrically conductive paths each made of an electrically conductive layer, the two electrically conductive paths connecting respectively the two first electrical contacts of the substrate layer to the two second electrical contacts of the microstructure, said at least one leg comprising dielectric layers embedding the corresponding electrically conductive layer, each leg having a lower foot connected to the substrate layer and a lateral arm extending upwardly from the lower foot to the microstructure for supporting the microstructure with respect to the substrate layer.

Claim 20

A method for forming a microbridge structure comprising microstructure suspended from a substrate layer by a micro support, the method comprising steps of: (a) providing the substrate layer with two first electrical contacts; (b) covering the substrate layer with a first temporary layer, patterning and etching first cavities in the first temporary layer to provide accesses to the two first electrical contacts of the substrate layer, covering the layers of the steps (a) to (b) with a first dielectric layer, and patterning and etching the first dielectric layer to provide accesses to the first electrical contacts of the substrate layer; (c) covering the layers of the previous steps (a) to (b) with a first electrically conductive layer; patterning and etching the first electrically conductive layer to provide two first electrically conductive paths extending respectively from the two first electrical contacts, the two first electrically conductive paths being parts of the micro support; covering the layers of the steps (a) to (c) with a second dielectric layer; and patterning and etching the first and second dielectric layers to embed the first electrically conductive layer except for contacts with the two first electrical contacts, the first and second dielectric layers being parts of the micro support; (d) covering the layers of the previous steps (a) to (c) with a second temporary layer, patterning and etching second cavities in the second temporary layer to provide accesses to the two second electrical contacts, and covering the layers of the steps (a) to (d) with a third dielectric layer; (e) covering the layers of the previous steps (a) to (d) with a sensing layer, patterning and etching the sensing layer to define a sensing area extending generally over the first electrically conductive paths, and patterning and etching the second and third dielectric layers to provide accesses to the two second electrical contacts; (f) covering the layers of the previous steps (a) to (e) with a second electrically conductive layer; patterning and etching the second electrically conductive layer to provide two second electrically conductive paths extending respectively from the two first electrically conductive paths to two electrical contacts of the sensing area, the second electrically conductive paths being parts of the micro support; covering the layers of steps (a) to (f) with a fourth dielectric layer to embed the sensing area and the second electrically conductive layer except for contacts with the two second electrical contact; and patterning and etching the third and fourth dielectric layers to shape the microstructure and upper parts of the micro support; and (g) removing the first and second temporary layers to reveal the micro support which extends generally underneath the microstructure, between the microstructure and the substrate layer.

Claim 21

A method for forming a microbridge structure comprising microstructure suspended from a substrate layer by a micro support, the method comprising steps of: (a) providing the substrate layer with two first electrical contacts; (b) covering the substrate layer with a first temporary layer, patterning and etching first cavities in the first temporary layer to provide accesses to the two first electrical contacts of the substrate layer, covering the layers of the steps (a) to (b) with a first dielectric layer, and patterning and etching the first dielectric layer to provide accesses to the first electrical contacts of the substrate layer; (c) covering the layers of the previous steps (a) to (b) with a first electrically conductive layer; patterning and etching the first electrically conductive layer to provide two first electrically conductive paths extending respectively from the two first electrical contacts, the two first electrically conductive paths being parts of the micro support; covering the layers of the steps (a) to (c) with a second dielectric layer; and patterning and etching the first and second dielectric layers to embed the first electrically conductive layer except for contacts with the two first electrical contacts, the first and second dielectric layers being parts of the micro support; (d) covering the layers of the previous steps (a) to (c) with a second temporary layer, patterning and etching second cavities in the second temporary layer to provide accesses to the two second electrical contacts, and covering the layers of the steps (a) to (d) with a third dielectric layer; (e) covering the layers of the previous steps (a) to (d) with a sensing layer, patterning and etching the sensing layer to define a sensing area extending generally over the first electrically conductive paths, and patterning and etching the second and third dielectric layers to provide accesses to the two second electrical contacts; (f) covering the layers of the previous steps (a) to (e) with a second electrically conductive layer; patterning and etching the second electrically conductive layer to provide two second electrically conductive paths extending respectively from the two first electrically conductive paths to two electrical contacts of the sensing area, the second electrically conductive paths being parts of the micro support; covering the layers of steps (a) to (f) with a fourth dielectric layer to embed the sensing area and the second electrically conductive layer except for contacts with the two second electrical contact; and patterning and etching the third and fourth dielectric layers to shape the microstructure and upper parts of the micro support; and (g) removing the first and second temporary layers to reveal the micro support which extends generally underneath the microstructure, between the microstructure and the substrate layer.