Education Research Group Falta

Join the surface physics team. You can research your topic in the laboratory using our equipment and microscopes. We always have a selection of Bachelor's and Master's theses. And if you can't find the right topic, you are also welcome to contact us.

Contact via Prof. J.Falta

 

Studentin arbeitet am LEEM
1. Nucleation of sputtered-grown Ga2O3 on Ru by TEM
Nucleation of sputtered-grown Ga2O3 on Ru by AFM

We will study the impact of the roughness of the Ru surface on the nucleation of Ga2O3.

The Growth of the samples will be performed using radio frequency (RF) sputtering of Ru and Ga2O3 .

The surface roughness of the Ru films will be tailored by annealing at different temperatures.

Ga2O3 films will be grown at different temperatures in order to study the nucleation process in detail.

For the characterization of the growth steps various techniques will be applied, such as scanning microscopy (AFM/STM), low energy electron diffraction (LEED) and x-ray photoemission spectroscopy (XPS).

Design and prototyping of a cross-bar device

Aims: Develop a working prototype of a resistive switching memory device using CeO2 and Ga2O3 and establishing a reliable design for RS switching devices and

Resistive switching refers to the ability of a material to change its electrical resistance between high and low states, a crucial property for next-generation random access memory (RAM). CeO2 and Ga2O3 are promising materials for resistive RAM (ReRAM), a new technology for future non-volatile memory.

The samples will be prepared using sputter deposition of ruthenium, sapphire and aluminum and characterizes by low-energy electron diffraction (LEED) and scanning electron microscopy (SEM) as well as atomic force microscopy (AFM).

Electrical measurements provide insight into the resistive switching characteristics. A new sample design is needed to avoid the conductive tips scratching the contact’s surface, and destroying the device easily. This resulted in low yield and problems with the repeatability of measurements. For this purpose  in a cross-bar geometry will be developed.

Adsorption of Ga on Ru 0001 using high-resolution LEED
Adsorption of Ga on Ru(0001) - Top view by AFM
Top view (by AFM)

The adsorption of Gallium on the Ruthenium (0001) surface will be studied using high-resolution low-energy electron diffraction (SPA-LEED) and microscopy (LEEM and AFM) and electron spectroscopy.

The aim is to establish an understanding of the evolution of the surface structure, morphology and the implications for surface chemistry, e.g. in catalysis.

Nucleation of sputtered-grown CeO2 on Ru(0001)
Nucleation of sputtered-grown CeO2 on Ru(0001)

We will investigate the nucleation process of CeO₂ on Ru(0001)/Al₂O₃(0001).
The samples will be prepared by radio frequency (RF) sputtering of ruthenium and cerium oxide.
We will compare this new growth approach to molecular beam epitaxy (MBE) which we studied previously for the same materials combination as illustrated in the figures on the right.
For the characterization of the preparation various techniques are used, such as scanning microscopy (AFM/STM), low energy electron diffraction (LEED) and X-ray photoemission spectroscopy (XPS). This project will provide insights into the growth mechanisms associated with these two distinct deposition techniques.