Patents Assigned to Mosel Viltelic, Inc.
  • Patent number: 5701013
    Abstract: The present invention provides a wafer metrology pattern integrating both overlay and critical dimension features for SEM or AFM measurements. The present invention provides an improved test mask target which contains lines measuring 0.25 .mu.m, 0.3 .mu.m, and 0.5 .mu.m. The spaces between the lines can be adjusted accordingly. The improved test mask target provides a pattern that combines the wafer critical dimension and box-in-box overlay targets into a single structure. As a result, the pattern may be used for both overlay and critical dimension verifications in a single AMF or SEM measurement. More precisely, wafer overlay and critical dimension disposition may be made simultaneously, reducing the need to perform multiple measurements at each testing step.
    Type: Grant
    Filed: June 7, 1996
    Date of Patent: December 23, 1997
    Assignee: Mosel Viltelic, Inc.
    Inventors: Liang-Choo Hsia, Thomas Chang