Date: 31.10.2017
Time: 13.00
Place: Dean Meeting Room
ABSTRACT
Auger electron spectroscopy (AES) is a very valuable tool for elemental characterization. It makes a very handy tool for analyzing features of nano – size in various samples. AES first started being used as an analytical tool around the 1960’s, even though the principle upon which it is based, the Auger effect was discovered in 1923. The characteristic signal for this technique comes from the top 0.4 – 5 nm of the sample surface (i. e. its depth resolution), while the electron beam diameter can be focused to diameters as low as 10 nm spot size. The technique that rivals it in performance and complements it in analysis is also X-ray photoelectron spectroscopy (often performed on the same apparatus), but the inability to focus the x-ray beam to diameters as low as 10 nm spot size gives AES a reputable position in the research world whenever considering analysis which require characterization of nano features. The applications of AES include fields like metallurgy (studies of segregation, characterizing nonmetallic inclusions), microelectronics technology (evaluating the raw material, checking the composition, uniformity, and thickness of thin films, etc.), heterogeneous catalysis, and corrosion science, among others. The focus of our team at the Institute of Metals and Technology in Ljubljana, Slovenia, was finding ways to achieve automatic interpretation of Auger electron spectra. Due to the complexity of the Auger spectrum itself, complete automatic interpretation of Auger spectra hasn’t yet been achieved. Even that little part of automatic interpretation which is possible is performed with a lot of error. The background and noise are regarded as the main hindering factors to this process, and as something which must be dealt with before any further steps can be considered. Through our work we have made a few steps forward in this direction by incorporating simulated spectra in the process, as well as using neural networks and Fourier analysis for the purpose of background definition and noise reduction. Also correlation was proposed as a tool for enhancing the signal, thus making it easier for any potential software to detect the peaks even when they are of low intensity, which means that it will be able to detect these elements at lower concentrations. As this is still an ongoing work, still more testing remains to be carried out in order to give the final verdict in this regard.
SHORT BIOGRAPHY
Besnik Poniku was born in 1982 in Pizren, Kosovo. He completed his primary and secondary education in his hometown. From September 1998 to June 2000 he lived in the USA where he completed his second and third year of High School at Franklin Pierce High School, Tacoma, Washington State. Besnik Poniku completed his Bachelor’s degree in Chemical Engineering at the Faculty of Mathematical and Natural Sciences, University of Prishtina, Kosovo, in 2005. The language of study was Albanian. In 2008 he earned a scholarship for continuing his postgraduate studies at the Jozef Stefan International Postgraduate School in Ljubljana, Slovenia. There he enrolled in the Nanosciences and Nanotechnologies study programme. The studies were summoned in January 2009, and he completed his Master’s degree in October 2010. The master thesis was titled: “Auger spectra recognition and modeling”. Immediately after that, at the same institution and the same study programme, he started pursuing his PhD degree. He completed his doctoral studies successfully in February 2015 under the mentorship of Prof. dr. Monika Jenko and co-mentorship of A/Prof. dr. Igor Belič. The doctoral thesis was titled: “Automated Auger electron spectra analysis”. The language of study for both master and PhD studies was English. Besnik Poniku worked at the Institute of Metals and Technology in Ljublana from the 16th of January 2009 until the 30th of April 2014, initially as a research assistant in the position of a chemical engineer, and later from November 2011 until the end as a Junior Researcher, a grant supported by the Slovenian Research Agency. There he was part of the Laboratory for Surface Analysis in the Physics and Chemistry of Materials department. The experimental work on Auger electron spectroscopy required for completing his studies was carried out in this institution. From September 2017 Besnik Poniku is part of the Department of Biomedical Engineering at the Faculty of Engineering of Karabuk University.
The complete bibliography of Besnik Poniku may be found here.