Methods and apparatuses for etch profile optimization by reflectance spectra matching and surface kinetic model optimization
US9996647B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 7, 2017 |
| Grant date | Jun 12, 2018 |
| Priority date | — |
| Expiry date | Sep 7, 2037 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2210/56
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Disclosed are methods of optimizing a computer model which relates the etch profile of a feature on a semiconductor substrate to a set of independent input parameters (A), via the use of a plurality of model parameters (B). In some embodiments, the methods may include modifying one or more values of B so as to reduce a metric indicative of the differences between computed reflectance spectra generated from the model and corresponding experimental reflectance spectra with respect to one or more sets of values of A. In some embodiments, calculating the metric may include an operation of projecting the computed and corresponding experimental reflectance spectra onto a reduced-dimensional subspace and calculating the difference between the reflectance spectra as projected onto the subspace. Also disclosed are etch systems implementing such optimized computer models.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.