In situ Raman spectroscopy during atomic layer deposition

Groep: CoCooN

Promotor:Roel Baets, Jolien Dendooven

Begeleiding:Ali RazaStéphane Clemmen,

Inlichtingen: tel. 09/264.43.42 of contacteer rechtstreeks een betrokken persoon (de contact-gegevens opvragen door op de naam te klikken)

Atomic layer deposition is a technique capable of conformally depositing a wide variety of materials on nearly any substrate with sub-nm thickness resolution. The initial nucleation of the layer is the most critical phase of the growth process, as it determines the crystallinity and overall morphology of the final coating. However, these very initial stages of deposition are also the most difficult to characterize, in view of the minute amount of material that has been deposited at that stage.

Raman spectroscopy is a characterization technique capable of identifying chemical compounds as well as their crystallinity. Recently, it was shown that chip-based Raman sensors could detect the presence of biological monolayers thanks to the greatly enhanced interaction length in dedicated photonic waveguides. This master thesis project aims at interfacing such a Raman sensor to an ALD reactor and measuring the Raman spectra of thin ALD layers “in situ”, i.e. in real-time during the deposition process. This approach will help to better understand the dynamics of the chemical surface processes taking place during the ALD process.

This project is primarily experimental. The student will have to design, assemble and test a system consisting of two parts: (1) a photonic chip, ball lens and holder positioned inside the ALD reactor, and (2) an external optical system capable of controlling the incidence angle of the excitation laser beam onto the ball lens. This will involve opto-mechanics and optical design.