Predictive wafer modeling based focus error prediction using correlations of wafers
US9707660B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 12, 2014 |
| Grant date | Jul 18, 2017 |
| Priority date | — |
| Expiry date | Jan 14, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2210/48
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
Predictive modeling based focus error prediction method and system are disclosed. The method includes obtaining wafer geometry measurements of a plurality of training wafers and grouping the plurality of training wafers to provide at least one training group based on relative homogeneity of wafer geometry measurements among the plurality of training wafers. For each particular training group of the at least one training group, a predictive model is develop utilizing non-linear predictive modeling. The predictive model establishes correlations between wafer geometry parameters and focus error measurements obtained for each wafer within that particular training group, and the predictive model can be utilized to provide focus error prediction for an incoming wafer belonging to that particular training group.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.