Method of fabricating a mems device
AssigneeTexas Instruments Incorporated
InventorSean Christopher O'Brien
Life of this patent
Estimating the term…
Abstract
A microelectromechanical system (MEMS) is comprised of a micromirror device attached to a semiconductor device. A first spacer layer is formed and patterned to form hinge via openings. A hinge metal is deposited above the first spacer layer to form the hinge and the hinge vias. A capping layer is formed above the hinge metal and hinge vias. A second spacer layer is formed above the capping layer and patterned to form a mirror via. The capping layer protects the hinge metal from the developer solution used in the patterning step. The capping layer is removed from within the mirror via opening. Another metal layer is deposited above the second spacer layer to form the mirror and the mirror via.
Claims13
A method of fabricating a microelectromechanical system (MEMS) device, comprising:
- depositing a first spacer layer above a substrate with circuits formed therein;
- patterning hinge via openings within the first spacer layer;
- depositing a hinge metal layer above the first spacer layer and within the hinge via openings to form a hinge and hinge vias;
- depositing a capping layer above the hinge metal layer and above the hinge vias;
- depositing a second spacer layer above the capping layer;
- patterning a mirror via opening within the second spacer layer, wherein the capping layer is exposed at a bottom of the mirror via opening;
- removing the capping layer exposed at the bottom of the mirror via opening;
- depositing a mirror metal within the mirror via opening and above the second spacer layer to form a mirror and mirror via, wherein the mirror via contacts that hinge metal layer;
- removing the first and second spacer layers and capping layer using an oxygen ash to release the hinge and the mirror.
A method of fabricating a digital micromirror device, comprising:
- depositing a first spacer layer above a substrate, the first spacer layer comprising a photoresist;
- patterning hinge via openings within the first spacer layer;
- depositing a hinge metal layer above the first spacer layer and within the hinge via openings to form a hinge and hinge vias;
- depositing a capping layer above the hinge metal layer, wherein the capping layer comprises a carbon material;
- depositing a second spacer layer above the capping layer, the second spacer layer comprising photoresist;
- patterning a mirror via opening within the second spacer layer to expose the capping layer, wherein the patterning step uses a developer solution, and wherein the capping layer prevents the developer solution from contacting the hinge metal layer;
- removing the capping layer within the mirror via opening using a plasma etch process after the patterning step;
- depositing a mirror metal within the mirror via and above the second spacer to form a mirror and mirror via, wherein the mirror metal contacts the hinge metal layer at a bottom of the mirror via;
- removing the first and second spacer layers and capping layer using an oxygen ash to release the hinge and the mirror.
Dependencies are inferred from the claim text.