Power MEMS Development
Abstract
In January we reported that the micro-cantilevers were stuck down to the substrate after fabrication. In the past, we have not seen this failure when we used devices fabricated on silicon-on-insulator (SOI) wafers and platinum (Pt) contacts. The two mechanisms we have come up with that would lead to this failure that also include new processes that were introduced specifically for this device process flow are 1) deformation of the bond metal in the anchor region or 2) charging of the cantilever during the reactive ion etch (RIE) step. In parallel with failure analysis to determine a root cause, we continue to develop a version 2 device (VC2.0), which is not subject to those two mechanisms. For the VC2.0 device, we are utilizing a plate and spring configuration successfully used in a previous project for an array of closely coupled optical MEMS devices to replace our single anchor "diving board" cantilever configuration used in the first version. A nominally 500 x 500 micronm plate suspended on all four sides with Si springs is fabricated using the SOI wafer (Figure 1.) The electrical routing and electrostatic drive electrode are pattered on a borosilicate glass wafer (Figure 2) which is thermally matched to the SOI wafer to eliminate misalignment during wafer bonding.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 2010
- Accession Number
- ADA514846
Entities
People
- John Burngarner
Organizations
- SRI International