Metrology test structure design and measurement scheme for measuring in patterned structures
US10359369B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 6, 2015 |
| Grant date | Jul 23, 2019 |
| Priority date | — |
| Expiry date | Feb 7, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2210/56
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A test structure is presented for use in metrology measurements of a sample pattern. The test structure comprises a main pattern, and one or more auxiliary patterns. The main pattern is formed by a plurality of main features extending along a first longitudinal axis and being spaced from one another along a second lateral axis. The one or more auxiliary patterns are formed by a plurality of auxiliary features associated with at least some of the main features such that a dimension of the auxiliary feature is in a predetermined relation with a dimension of the respective main feature. This provides that a change in a dimension of the auxiliary feature from a nominal value affects a change in non-zero order diffraction response from the test structure in a predetermined optical measurement scheme, and this change is indicative of a deviation in one or more parameters of the main pattern from nominal value thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.