Reducing microelectromechanical systems stiction by formation of a silicon carbide layer

摘要

A mechanism is provided for reducing stiction in a MEMS device by forming a near-uniform silicon carbide layer on silicon surfaces using carbon from TEOS-based silicon oxide sacrificial films used during fabrication. By using the TEOS as a source of carbon to form an antistiction coating, all silicon surfaces can be coated, including those that are difficult to coat using standard self-assembled monolayer (SAM) processes (e.g., locations beneath the proof mass). Controlled processing parameters, such as temperature, length of time for annealing, and the like, provide for a near-uniform silicon carbide coating not provided by previous processes.

主权项

1. A method for manufacturing a microelectromechanical systems (MEMS) device, the method comprising:
forming a first silicon layer over a substrate; forming a sacrificial layer over the first silicon layer, wherein the sacrificial layer comprises silicon oxide deposited using tetraethyl orthosilicate (TEOS) gas; annealing the first silicon layer and the sacrificial layer wherein said annealing comprises heating the first silicon layer and the sacrificial layer to a temperature sufficient to form a silicon carbide layer at an interface region between the first silicon layer and the sacrificial layer, wherein the silicon carbide layer comprises carbon provided by the sacrificial layer.