Apparatus and methods for semiconductor IC failure detection
US7067335B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 2, 2002 |
| Grant date | Jun 27, 2006 |
| Priority date | — |
| Expiry date | Oct 2, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/307
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improved voltage contrast test structure is disclosed. In general terms, the test structure can be fabricated in a single photolithography step or with a single reticle or mask. The test structure includes substructures which are designed to have a particular voltage potential pattern during a voltage contrast inspection. For example, when an electron beam is scanned across the test structure, an expected pattern of intensities are produced and imaged as a result of the expected voltage potentials of the test structure. However, when there is an unexpected pattern of voltage potentials present during the voltage contrast inspection, this indicates that a defect is present within the test structure. To produce different voltage potentials, a first set of substructures are coupled to a relatively large conductive structure, such as a large conductive pad, so that the first set of substructures charges more slowly than a second set of substructures that are not coupled to the relatively large conductive structure. Mechanisms for fabricating such a test structure are also disclosed. Additionally, searching mechanisms for quickly locating defects within such a test structure, as well…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.