By using state-of-the-art methods, you will develop novel semiconductors, specifically ZnSnN2; in general, you will learn how to control and tailor the functional properties of materials in order to design novel solar cells.
The II-IV-N2 is a class of novel earth-abundant semiconductors promising to bring a renewal into the next-generation solar cells. In particular, ZnSnN2 exhibits the optical band gap that is well suited for the top-part of the tandem solar cell together with Si; so that such tandem device may deliver higher efficiencies in comparison with that in the Si cell alone. In this project, you will be trained to use state-of-the-art instruments at the UiO Micro- and nanotechnology laboratory (MiNaLab - https://www.mn.uio.no/fysikk/english/research/minalab/), in order to fabricate and characterize ZnSnN2 thin films. As-grown ZnSnN2 typically exhibits unacceptably high electron carrier densities for appropriate solar cell designs. Thus, the main goal of the project is to develop strategies for controlling the electron density in ZnSnN2 and, potentially, in other earth-abundant materials of the II-IV-N2 family. Examples of such strategies include off-stoichiometric growth and in-situ impurity doping.
Figure 1. (left) the lattice structure of ZnSnN2 as simulated by Dr Y. Frodason and (right) the Flextura cluster for this film growth - photo by J. Borgersen. The Flextura cluster will be used to synthesize ZnSnN2 samples in this project.
The Flextura cluster for thin film growth will be used for the sample fabrication. The x-ray diffractometer and the Hall effect measurement setup will be used for determining structural and electrical properties, respectively. The optical transmission and cathodoluminescence will be used to measure the optical properties. Altogether, you will learn how to control and tailor the functional properties of materials in order to design novel solar cells.
Our team at the Light and Electricity from Novel Semiconductors (LENS) group develops modern semiconductor materials for next-generation solar cells, power electronics, photonics, and quantum technologies. Please visit our home page for further details (https://www.mn.uio.no/fysikk/english/research/groups/semiconductors/).
Supervisors: Vegard S. Olsen, Andrej Yu. Kuznetsov, Lasse Vines.