Monitoring Defects by Scanning Electron Microscope Beam Charging
Original Publication Date: 1988-Nov-01
Included in the Prior Art Database: 2005-Feb-15
By creating on-chip monitors with known charge/discharge characteristics, a variety of defect types are quickly detected and their locations easily determined. This technique is used as a low cost quality assessment means and to identify defect locations for failure analysis. The basic approach of this technique is to utilize the electron beam charging of exposed conductive features on the surface of in- process device structures. In a scanning electron microscope (SEM) environment, this beam charging causes a variation in the secondary electron collection, creating a SEM picture in which the appearance of those conductive features connected to, or containing, a defect varies with respect to defect-free conductive features.