MEMS device including coil structure with corrugated polymer film
A micro electro mechanical system (MEMS) device and a method for manufacturing the same are provided. The MEMS device includes a substrate, a polymer film on the substrate and having a lower surface facing toward the substrate, a cavity passing through the substrate, and coil structures on the substrate and in the polymer film. The polymer film includes a corrugation pattern on the lower surface of the polymer film. A portion of the polymer film is exposed in the cavity.
1. A micro electro mechanical system (MEMS) device, comprising:
a substrate;
a polymer film on the substrate and having a lower surface facing toward the substrate, wherein the polymer film comprises a corrugation pattern on the lower surface of the polymer film;
a cavity passing through the substrate, wherein a portion of the polymer film is exposed in the cavity;
coil structures on the substrate and in the polymer film;
a dielectric layer between the substrate and the polymer film, wherein the cavity passes through the dielectric layer; and
an oxide layer between the dielectric layer and the substrate.
2. The MEMS device according to claim 1 , wherein the corrugation pattern of the polymer film is exposed in the cavity.
3. The MEMS device according to claim 1 , wherein the corrugation pattern of the polymer film comprises convex portions separated from each other, the convex portions protrude toward the cavity.
4. The MEMS device according to claim 1 , wherein the polymer film has an upper surface opposite to the lower surface, the upper surface of the polymer film comprises a flat surface portion, and the flat surface portion overlaps the corrugation pattern along a longitudinal direction.
5. The MEMS device according to claim 1 , wherein the dielectric layer has a lower surface facing toward the substrate, a portion of the lower surface of the dielectric layer is exposed in the cavity.
6. The MEMS device according to claim 1 , wherein the oxide layer and the dielectric layer comprise different materials.
7. The MEMS device according to claim 1 , wherein the cavity passes through the oxide layer.
8. The MEMS device according to claim 1 , further comprising a metal layer between the substrate and the polymer film, a portion of the metal layer is exposed in the cavity.