In-line EUV mask characterization and modeling

The title of the PhD position is “in-line EUV mask characterization and modeling”.

The topic falls in the general domains of material science and metrology.

The photomask is an integral part of the lithographic process, which is used to create the nano patterns on computer chips. With the development of EUV lithography the mask transformed into a complex object of many materials that must come together in a precise fashion to enable it to function properly. Even though the resounding success of EUV lithography there are still many aspects of EUV masks that are not fully understood and therefore not fully exploited. One such aspect is the variability in the constituting material layers, how they impact the performance and how they evolve over the life cycle of the mask. The aim of this topic is to unravel the EUV mask structure by engaging non-destructive experimental techniques ensuring the masks stay usable for exposures. Techniques may include x-ray reflectivity, x-ray photoelectron spectroscopy, critical dimension secondary electron microscopy or the capabilities of imec’s Attolab. This topic encourages interdisciplinary collaborations between imec’s patterning, material and characterization departments. You will implement the learnings on the EUV mask structure from the application of these techniques in a mask model for lithography simulation to assess the impact on the edge placement error on-wafer. Finally, you will validate the model predictions against data collected from wafer exposures or aerial image metrology. 

As part of the Imaging and Reticles competence team within the Advanced Pattering department of imec here in Leuven, you will work alongside a group of dedicated researchers, who study the optical image formation process in the most advanced lithography system in the world and its dependency on all aspects of the photomask. In addition, you will be enrolled in the Katholieke Universiteit Leuven during your PhD studies.