The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Mar. 02, 1993

Filed:

Jul. 05, 1991
Applicant:
Inventors:

Haroon Ahmed, Cambridge, GB;

Simon Blythe, Cambridge, GB;

Beatrice Fraboni, Bologna, IT;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ; H01J / ;
U.S. Cl.
CPC ...
250310 ; 250307 ; 250397 ;
Abstract

The structure of a multilayered integrated circuit is determined by removing successive layers of the circuit. Following removal of each layer, the revealed surface is scanned by an electron beam. The intensity of backscattered or secondary electrons is detected by a first or second detector respectively. From the detected electron intensities, image processing circuitry derives a representation of the integrated circuit surface scanned. Where the surface of the integrated circuit is a flat layer of semiconductor substrate material having implanted doped areas, the surface is covered with a metallisation layer providing a Schottky barrier junction with the doped areas. Electron beam scanning of the metallisation layer induces a current at this junction which is monitored and processed to derive a representation of the outline of the doped implanted areas.


Find Patent Forward Citations

Loading…