E-beam inspection apparatus and method of using the same on various integrated circuit chips
AssigneePDF Solutions, Inc.
InventorsIndranil De, Christopher Hess, Dennis J. Ciplickas
Life of this patent
Estimating the term…
Abstract
The present invention discloses an e-beam inspection tool, and an apparatus for detecting defects. In one aspect is described an apparatus for detecting defects that includes a focusing column that accelerates the e-beam and separately, for each of the plurality of predetermined locations, focuses the e-beam to a predetermined non-circular spot that is within the predetermined surface area of each of the plurality of predetermined locations based upon the major axis.
Claims21
An apparatus for detecting defects in an integrated circuit, wherein the integrated circuit includes a plurality of predetermined locations each having a predetermined surface area and a major axis and the apparatus comprising:
- a target holder for holding said integrated circuit;
- an e-beam source that directs an e-beam toward each of the plurality of predetermined locations on the integrated circuit;
- a focusing column that accelerates the e-beam and separately, for each of the plurality of predetermined locations, focuses the e-beam to a predetermined narrow non-circular spot that is within the predetermined surface area of each of the plurality of predetermined locations based upon the major axis, the focusing column including a condensor lens, an objective lens and a Wehnelt, wherein the condensor lens and the objective lens are disposed between the e-beam source and the Wehnelt, and wherein the Wehnelt is disposed in a location of the focusing column that receives the e-beam and the secondary electrons;
- and
- a detector that detects a voltage contrast image of secondary electrons emitted from the integrated circuit after the e-beam strikes each of the plurality of predetermined locations of the integrated circuit.
An apparatus for detecting defects in an integrated circuit, wherein the integrated circuit includes a plurality of predetermined locations and the apparatus comprising:
- a target holder for holding said integrated circuit;
- an e-beam source that directs an e-beam toward each of the plurality of predetermined locations on the integrated circuit;
- a focusing column that accelerates the e-beam of electrons and focuses the e-beam to each of the plurality of predetermined locations, the focusing column including a condensor lens, an objective lens and a Wehnelt;
- and
- a detector that obtains e-beam excited measurements, without continuously scanning, from the plurality of locations by selectively sampling fewer than ten pixels from an e-beam pad associated with each of said plurality of locations.
An apparatus for detecting defects in an integrated circuit, wherein the integrated circuit includes a plurality of predetermined locations and the apparatus comprising:
- a target holder for holding said integrated circuit;
- an e-beam source that directs an e-beam of electrons toward each of the plurality of predetermined locations on the integrated circuit;
- a focusing column that accelerates the e-beam of electrons and focuses the e-beam to each of the plurality of predetermined locations, the predetermined locations having a plurality of e-beam skip zones there between, thereby allowing the focusing column to skip at least 10% of its overall scan length, the focusing column including a condensor lens, an objective lens and a Wehnelt;
- and
- a detector that obtains e-beam excited measurements, without continuously scanning, from the plurality of locations from an e-beam pad associated with each of said plurality of locations.
Dependencies are inferred from the claim text.