Chemical and electrochemical treatments for accelerating cavities – Master Thesis Eduard Chyhyrynets

Author: Eduard Chyhyrynets ; Type of thesis: Master Thesis
Abstract: During my master course I worked mainly in chemical laboratory to proceed chemical and electrochemical treatment protocols that involve several steps, and they vary from Niobium 6 GHz cavities to modeling square copper samples.
My main task was dedicated to the learning different techniques, that were applied to the problem of ARIES project, that makes the second part of this thesis. Here is the list of techniques: electropolishing, chemical polishing, cleaning processes and SEM, EDS, profilometer equipment.
To investigate the role of the substrate in the SRF performances, several surface treatments were applied to a certain amount of copper samples. Here is a list of the treatments involved: chemical polishing, electropolishing, combination of chemical and electrochemical treatment and to mechanical treatment (tumbling). The quality of the sample’s surface were studied and evaluated by visual observation, under SEM, EDS, profilometer and by calculating average removal thickness.
The protocol optimization was done on flat samples in order to study the critical points of the processes and avoid wasting the real samples. In the nearest future, the quality of the work will be evaluated by comparing the performance of Nb thin film on different substrate preparation.