Patent · US Expired

Scanning electron microscope based parametric testing method and apparatus

US4978908A · kind A · utility

16Cited by
5References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 22, 1989
Grant dateDec 18, 1990
Priority date
Expiry dateMar 22, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/305
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A scanning electron microscope (28) is connected to a test structure (48) formed on a semiconductor wafer. The test structure (48) comprises a plurality of first parallel structures (54) and a plurality of second parallel structure (56) transverse to and interlocking with the first structures (54). An island (60) is formed within a grid (58) formed by the structures (54-56) and is separated therefrom. An electron beam (38) from the scanning electron microscope (28) is aimed at the structure (48) and secondary electrons emitted therefrom are visually displayed on a monitor (44). The visual display (47) provides information on whether the island (60) is electrically separated from the mesh (58) or shorted thereto by comparing the intensity of the various islands (60).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.