| Zugriffsnummer | 22162 |
| Dokumenttyp | Zeitschriftenartikel |
| Peer Review | unbekannt |
| Sprache | Englisch |
| Titel | Mathematical aspects of scatterometry - an optical metrology technique |
| Autor(in); Institution |
Groß, Hermann; 8.4, Mathematische Modellierung und Datenanalyse, PTB-Berlin
Rathsfeld, Andreas; Weierstraß-Institut für Angewandte Analysis und Stochastik, Berlin, GERMANY
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| Quelle/Jahr | Weierstraß-Institut für Angewandte Analysis und Stochastik: Annual research report: 2007 (2008), 18 - 23 |
| ISSN | 1437-7489 |
| Verlag | Berlin: WIAS |
| Freie Schlagworte | lithograhy ; scatterometry ; inverse problem |
| Zusammenfassung | The breathtaking development of nanotechnology requires to design and control components with smaller and smaller details. In particular, the fabrication of up-to-date computer chips and storage devices by lithographic manufacturing processes is impossible without new accurate measurement techniques coping with the tiny details of masks and wafers. A promising approach for chip production of the next generation is extreme ultrviolet (EUV) lithography. Usual methods of mask measurements are scanning electron microscopy (SEM) or atmic force microscopy (AFM). Unfortunately, these methods do not necessarily yield the same results. Furthermore, both have their specific limitations. Scatterometry is an independent and alternative technique for the characterization of mask profiles. In scatterometry, the sample is illuminated by a light with a wavelength comparable with or even larger than the details to be determined. Of course, instead of a nice image, a picture of a complicated scattered wave pattern is measured and the geometry must be reconstructed by solving an inverse problem for the time-harmonic Maxwell equations. More precisely, using a numerical algorithm, a geometry with such details is to be sought for which the diffraction pattern of the numerical simulation coincides with the measured pattern. If this inverse problem is solved, then scatterometry provides a new indirect and nondestructive measurement method. |
