Layer processing
US6726767B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 22, 2001 |
| Grant date | Apr 27, 2004 |
| Priority date | — |
| Expiry date | Feb 22, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC30B25/186
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Layer processing to grow a layer structure upon a substrate surface comprises supplying a vapor mixture stream to the substrate (28) to deposit constituents, monitoring growth with an ellipsometer (12) and using its output in real-time growth control of successive pseudo-layers. A Bayesian algorithm is used to predict a probability density function for pseudo-layer growth parameters from initial surface composition, growth conditions and associated growth probabilities therewith, the function comprising discrete samples. Weights are assigned to the samples representing occurrence likelihoods based on most recent sensor output. A subset of the samples is chosen with selection likelihood weighted in favor of samples with greater weights. The subset provides a subsequent predicted probability density function and associated pseudo-layer growth parameters for growth control, and becomes a predicted probability density function for a further iteration of pseudo-layer growth.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.