LMGP Seminar -02/09/2016 - Kevin Rietwyk

Dr. Kevin Rietwyk

Department of Chemistry, Center for Nanotechnology & Adv. Mater., Bar Ilan niversity

Abstract
Thin film electronics is a rapidly growing technology that offers a range of device functionalities not possible with conventional metal-oxide-semiconductor technology such as printable, flexible and transparent electronics. The operation of thin-film electronic devices is dictated by the band alignment at the interfaces of the various layers. While a number of methods for measuring the depth profile of energetics at interfaces have emerged, these are typically arduous to perform and involve the use of ultra-high vacuum, complicated sample preparation and/or suffer from poor resolution.
To address these shortcomings we have developed a method to directly map the depth profile of energetics at an interface in air by growing a sample with an intentional thickness gradient and correlating the surface potential measured using scanning Kelvin probe to the thickness at each point. Our approach enjoys very high spatial (3 nm) and energy resolution (5 meV), superior to other methods. In addition, it is non-destructive and rapid, enabling parallel analysis with complimentary analysis techniques and the characterisation of multiple layers within devices in order to develop a complete band diagram.

Short CV
Dr Kevin Rietwyk completed his PhD in physics during 2014 at La Trobe University, Australia, on the topic of “Functionalisation of semiconductor surfaces and surface transfer doping”. The focus of this work was to modify the electronic properties of conventional semiconductor surfaces and investigate their electronic response to adlayers of molecular dopants. Kevin is currently a post-doctoral researcher in the Zaban laboratory in Bar-Ilan University, Israel. The group employs combinatorial research practices to discover new metal oxide compounds for photovoltaic applications. In 2015 he was awarded and commenced a Marie Curie Individual Fellowship entitled, “Pro-Oxides”, the aim of which is to determine the correlation between the electronic properties of metal oxides and their stoichiometry and to establish the alignment of energy-levels at all metal oxide interfaces.