METHOD OF FORMING PLANAR SACRIFICIAL MATERIAL IN A MEMS DEVICE

摘要

The present invention generally relates to a method of fabricating a MEMS device. In the MEMS device, a movable plate is disposed within a cavity such that the movable plate is movable within the cavity. To form the cavity, sacrificial material may be deposited and then the material of the movable plate is deposited thereover. The sacrificial material is removed to free the mov able plate to move within the cavity. The sacrificial material, once deposited, may not be sufficiently planar because the height difference between the lowest point and the highest point of the sacrificial material may be quite high. To ensure the movable plate is sufficiently planar, the planarity of the sacrificial material should be maximized. To maximize the surface planarity of the sacrificial material, the sacrificial material may be deposited and then conductive heated to permit the sacrificial material to reflow and thus, be planarized.

主权项

1. A method of forming a MEMS device, comprising:
depositing a sacrificial layer over a substrate; conduction heating the substrate and sacrificial layer to reflow the sacrificial layer and substantially planarized the sacrificial layer; forming a movable plate over the sacrificial layer; defining a cavity enclosing the sacrificial layer and the movable plate; and removing the sacrificial layer from the cavity.