HYBRID MEMS BUMP DESIGN TO PREVENT IN-PROCESS AND IN-USE STICTION

摘要

A micro-electro-mechanical systems (MEMS) device and method for forming a MEMS device is provided. A proof mass is suspended a distance above a surface of a substrate by a fulcrum. A pair of sensing plates are positioned on the substrate on opposing sides of the fulcrum. Metal bumps are associated with each sensing plate and positioned near a respective distal end of the proof mass. Each metal bump extends from the surface of the substrate and generally inhibits charge-induced stiction associated with the proof mass. Oxide bumps are associated with each of the pair of sensing plates and positioned between the respective sensing plate and the fulcrum. Each oxide bump extends from the first surface of the substrate a greater distance than the metal bumps and acts as a shock absorber by preventing the distal ends of the proof mass from contacting the metal bumps during shock loading.

主权项

1. A method for forming a micro-electro-mechanical systems (MEMS) device, the method comprising:
providing a substrate; forming a metal layer over the substrate; patterning the metal layer to form a pair of sensing plates and a plurality of metal bumps, wherein a pivot axis of a proof mass is defined between the pair of sensing plates, and wherein each of the plurality of metal bumps are positioned proximate to a respective distal end of the proof mass, wherein each metal bump generally inhibits charge-induced stiction associated with the proof mass; forming an oxide layer over the substrate; and patterning the oxide layer to form an oxide bump associated with each of the pair of sensing plates, wherein each oxide bump is positioned between the respective sensing plate and the pivot axis, and wherein each oxide bump generally acts as a shock absorber by preventing the distal ends of the proof mass from contacting the metal bumps during shock loading.