ACCURACY OF THIN-FILM STRESS MEASUREMENTS WITH C-SI MICROBEAMS FABRICATED BY DRY-ETCHING

Thin Al, Cr, and W films were deposited on monocrystalline (100) Si mi crobeams fabricated by a SCREAM-like dry etching process. Curvature me asurements and three-dimensional finite element method mechanical simu lations of the composite microbeams were combined to evaluate the resi dual mechanical stress in the metallic films. Factors limiting the mea surement accuracy are analyzed. It is shown that the measurement accur acy is largely dependent on microloading effects during the Si isotrop ic etching step necessary to release the microbeams from the substrate . (C) 1997 American Vacuum Society. [S0734-211X(97)03705-0].