/Photoelectron yield of resist materials for EUV lithography

Photoelectron yield of resist materials for EUV lithography

Leuven | More than two weeks ago

Shedding light on electronic processes occurring in extreme ultraviolet lithography

The electron yield is a key parameter that quantifies the magnitude of electronic processes occurring in photoresists during exposure to extreme ultraviolet (EUV, 13.5 nm wavelength) light. In EUV lithography, the patterning of photoresist is achieved by a cascade of low energy electrons generated by few primary photoelectrons. It is believed that photoresists with high electron yield are more efficient in generating the secondary electron cascade, which could lead to higher sensitivity, lower dose and increased throughput. However, there is not yet enough experimental evidence to confirm this hypothesis. For this reason, at imec we are exploring state-of-the-art photoresists (polymer-based and metal-oxide-based) by measuring the photocurrent generated during the exposure to light in the EUV wavelength. The outcome of this work is relevant not only for EUV but for all next generation nano-fabrication methods which will be based on electron-mediated exposure, such as electron-beam lithography.
During the internship, the candidate will prepare thin films (<= 30 nm) of photoresists actually used in the fabrication of next generation integrated circuits. Then, the candidate will learn to measure the photocurrent generated in situ by the photo-induced electron emission. Additional characterization techniques (ellipsometry, infrared spectroscopy and reflectivity) will be also employed to understand and explain the underlying chemical processes that cause the transition from unexposed to exposed photoresist. The applicant should be motivated and willing to work in a cleanroom environment and handling chemicals. An academic background in chemistry, condensed matter physics, or chemical physics is required. The candidate is also expected to present the findings of his internship as written thesis and/or in the form of imec internal dissertation. This position is only open to master’s students who have not received their degree yet.


Type of project: Internship, Thesis, Combination of internship and thesis

Duration: 4-9 months

Required degree: Master of Engineering Technology, Master of Science, Master of Engineering Science

Required background: Chemistry/Chemical Engineering, Electrotechnics/Electrical Engineering, Materials Engineering, Nanoscience & Nanotechnology, Physics

Supervising scientist(s): For further information or for application, please contact: Roberto Fallica (Roberto.Fallica@imec.be) and Ivan Pollentier (Ivan.Pollentier@imec.be)

Only for self-supporting students.