Work in progress

I now started a new project for my PhD Thesis. I try to work with Germanane, wich is a 2d material composed of Germanium atoms in one layer with H-atoms at the dangling bonds. At first I have to produce the Germanane, therefor I grow a zintl phase of CaGe₂, the interlayered Ca is then eliminated in an etching prozess to only leave a stack of Germanane layers. The possibility to do it that way has been shown by other reasearchers befor, for example by Dr. Vogg Adv. Mat. 12 (2000). As soon as the germanane production prozess is optimezed I will start to characterize these sheets.

I mainly study chemical reactions on surfaces and most of them as chemicurrents. My surfaces are thin metal films on Silicon substrates which form a Schottky diode. Using Schottky diodes allows to detect only hot charge carriers, so thermally induced charge transfer is mostly eliminated. More details on the process can be found here.

In a first experiment I use a well known Schottky diode by using Silver as the metal film. To keep the reaction as simple as possible I use atomic hydrogene which reacts on the metal surface. The thin silver film is grown epitaxily onto the Silicon substrate in an evaporation chamber and then the diode is transferred into my reaction chamber. This is necessary because i use high gas pressures and therefor need a rather small chamber. The atomic hydrogene is produced in a hydrogene source which dissociates molecular hydrogen to atomic hydrogen in a very small capillary. Then the atomic hydrogene traverses a light blocker befor reaching the sample.

In the next steps different structures of the metal film will be used. First experiments have been done using printed Silver-nanoparticles in rows or dot structures, those experiments are done in a cooperation with NETZ.

Curriculum vitae

Scientific Publications

Chemicurrent measurements using alkali metal covered Pd/p-Si(001) Schottky diodes
D. Krix, K. Huba, and H. Nienhaus, Journal of Vacuum Science and Technology A 27 (2009) 918.

Ultrathin K/p-Si(001) Schottky diodes as detectors of chemically generated hot charge carriers
K. Huba, D. Krix, C. Meier, and H. Nienhaus, Journal of Vacuum Science and Technology A 27 (2009) 889.

Adjustments of wear particle size distribution of DLC coatings for tribological metal-on-metal pairung in artificial hip joints
B. Stamm, B. Küzün, O. Filipov, S. Reuter, I. Erdmann, F. Deuerler, D. Krix, K. Huba, H. Nienhaus, and V. Buck, Materialwissenschaft und Werkstofftechnik (Materials Science and Engineering Technology)  40 (2009) 98.